ALTER PROCEDURE (SQL - native)

Invocation

This statement can only be dynamically prepared only if DYNAMICRULES run behavior is implicitly or explicitly specified.

Authorization

The privilege set that is defined below must include at least one of the following:

• Ownership of the procedure
• The ALTERIN privilege on the schema
• SYSADM authority
• SYSCTRL authority
• System DBADM

The authorization ID that matches the schema name implicitly has the ALTERIN privilege on the schema.

If the authorization ID that is used to alter the procedure has installation SYSADM authority, the procedure is identified as system-defined procedure when the procedure definition is reevaluated.

Additional privileges might be required in the following situations:

• If SQL-routine-body is specified, the privilege set must include the privileges that are required to execute the statements in SQL-routine-body.
• If a user-defined type is referenced (as the data type of a parameter or SQL variable), the privilege set must also include at least one of the following privileges or authorities:
• If a distinct type is referenced (i.e., as the data type of a parameter or an SQL variable), the privilege set must include at least one of the following:
  • Ownership of the distinct type
  • The USAGE privilege on the distinct type
  • SYSADM authority
  
• If the procedure uses a table as a parameter, the privilege set must also include at least one of the following privileges or authorities:
  • Ownership of the table
  • The SELECT privilege on the table
  • SYSADM authority
• If you specify the WLM ENVIRONMENT FOR DEBUG MODE clause, RACF® or an external security product is invoked to check the required authority for defining programs in the WLM environment. If the WLM environment access is protected in RACF, the privilege set must include the required authority.
• When defining a new version of a procedure (using the ADD VERSION clause) or when replacing an existing version (using the REPLACE VERSION clause), the privilege set must include the required authorization to add a new package or a new version of an existing package depending on the value of the BIND NEW PACKAGE field on installation panel DSNTIPP, or the privilege set must include SYSADM or SYSCTRL authority.

Additional authorization may be required on the SYSDUMMYx tables depending on the content of the procedure definition. See SYSDUMMYx tables.

Description

procedure-name

Identifies the procedure to alter. The procedure that is identified in procedure-name must exist at the current server.

ACTIVE VERSION or ALL VERSIONS or VERSION routine-version-id

Identifies the version of the procedure that is to be changed, replaced, or regenerated depending on whether the ALTER, REPLACE, or REGENERATE keyword is specified.

Important: Do not create additional versions of procedures that are supplied with DB2 by specifying the VERSION keyword. Only versions that are supplied with DB2 are supported. Additional versions of such routines cause the installation and configuration of the supplied routines to fail.

ACTIVE VERSION

Specifies that the currently active version of the procedure is to be changed, replaced, or regenerated.

ACTIVE VERSION is the default value.

VERSION routine-version-id

Identifies the version of the procedure that is to be changed, replaced, or regenerated. routine-version-id is the version identifier that is assigned when the version is defined. routine-version-id must identify a version of the specified procedure that exists at the current server.

ALTER

Specifies that a version of the procedure is to be changed.

When you change a procedure to add or replace a version of the procedure, any option that is not explicitly specified will use the existing value from the version of the procedure that is being changed.

REPLACE

Specifies that a version of the procedure is to be replaced.

Binding the replaced version of the procedure might result in a new access path even if the routine body is not changed.

When you replace a procedure, the data types, CCSID specifications, and character data attributes (FOR BIT/SBCS/MIXED DATA) of the parameters must be the same as the attributes of the corresponding parameters for the currently active version of the procedure. For options that are not explicitly specified, the system default values for those options are used, even if those options were explicitly specified for the version of the procedure that is being replaced. This is not the case for versions of the procedure that specified DISABLE DEBUG MODE. If DISABLE DEBUG MODE is specified for a version of a procedure, it cannot be changed by the REPLACE clause.

ADD VERSION routine-version-id

Specifies that a new version of the procedure is to be created. routine-version-id is the version identifier for the new version of the procedure. routine-version-id must not identify a version of the specified procedure that already exists at the current server.

When a new version of a procedure is created, the comment that is recorded in the catalog for the new version will be the same as the comment that is in the catalog for the currently active version.

When you add a new version of a procedure the data types, CCSID specifications, and character data attributes (FOR BIT/SBCS/MIXED DATA) of the parameters must be the same as the attributes of the corresponding parameters for the currently active version of the procedure. The parameter names can differ from the other versions of the procedure. For options that are not explicitly specified, the system default values will be used.

ACTIVATE VERSION routine-version-id

Specifies the version of the procedure that is to be the currently active version of the procedure. routine-version-id is the version identifier that is assigned when the version of the procedure is defined. The version that is specified with routine-version-id is the version that will be invoked by the CALL statement, unless the value of the CURRENT ROUTINE VERSION special register overrides the currently active version of the procedure when the procedure is invoked. routine-version-id must identify a version of the procedure that already exists at the current server.

REGENERATE

Regenerates a version of the procedure. When DB2 maintenance is applied that changes how an SQL procedure is generated, the procedure might need to be regenerated to process the maintenance changes.

REGENERATE automatically rebinds, at the local server, the package for the SQL control statements for the procedure and rebinds the package for the SQL statements that are included in the procedure body. If a remote bind is also needed, the BIND PACKAGE COPY command must be explicitly done for all of the remote servers.

REGENERATE is different from a REBIND PACKAGE command where the SQL statements are rebound (i.e. to generate better access paths for those statements), but the SQL control statements in the procedure definition remain the same.

DROP VERSION routine-version-id

Drops the version of the procedure that is identified with routine-version-id. routine-version-id is the version identifier that is assigned when the version is defined. routine-version-id must identify a version of the procedure that already exists at the current server and must not identify the currently active version of the procedure. Only the identified version of the procedure is dropped.

When only a single version of the procedure exists at the current server, use the DROP PROCEDURE statement to drop the procedure. A version of the procedure for which the version identifier is the same as the contents of the CURRENT ROUTINE VERSION special register can be dropped if that version is not the currently active version of the procedure.

(parameter-declaration,…)

Specifies the number of parameters of the procedure, the data type and usage of each parameter, and the name of each parameter for the version of the procedure that is being defined or changed. The number of parameters and the specified data type and usage of each parameter must match the data types in the corresponding position of the parameter for all other versions of this procedure. Synonyms for data types are considered to be a match.

IN, OUT, and INOUT specify the usage of the parameter. The usage of the parameters must match the implicit or explicit usage of the parameters of other versions of the same procedure.

IN

Identifies the parameter as an input parameter to the procedure. The value of the parameter on entry to the procedure is the value that is returned to the calling SQL application, even if changes are made to the parameter within the procedure.

IN is the default.

OUT

Identifies the parameter as an output parameter that is returned by the procedure. If the parameter is not set within the procedure, the null value is returned.

INOUT

Identifies the parameter as both an input and output parameter for the procedure. If the parameter is not set within the procedure, its input value is returned.

parameter-name

Names the parameter for use as an SQL variable. The name cannot be the same as the name of any other parameter-name for this version of the procedure. The name of the parameter in this version of the procedure can be different than the name of the corresponding parameter for other versions of this procedure.

built-in-type

Specifies the data type of the parameter. See CREATE PROCEDURE (SQL - native) for more information on data type specifications.

distinct-type-name

The data type of the input parameter is a distinct type. Any length, precision, scale, subtype, or encoding scheme attributes for the parameter are those of the source type of the distinct type. The distinct type must not be based on a LOB data type.

NOT DETERMINISTIC or DETERMINISTIC

Specifies whether the procedure returns the same results each time it is called with the same IN and INOUT arguments.

NOT DETERMINISTIC

The procedure might not return the same result each time it is called with the same IN and INOUT arguments, even when the data that is referenced in the database has not changed.

NOT DETERMINISTIC is the default.

DETERMINISTIC

The procedure always returns the same results each time it is called with the same IN and INOUT arguments if the data that is referenced in the database has not changed.

DB2 does not verify that the procedure code is consistent with the specification of DETERMINISTIC or NOT DETERMINISTIC.

MODIFIES SQL DATA, READS SQL DATA, or CONTAINS SQL

Specifies the classification of SQL statements and nested routines that this routine can execute or invoke. The database manager verifies that the SQL statements issued by the procedure, and all routines locally invoked by the routine, are consistent with this specification; the verification is not performed when nested remote routines are invoked. For the classification of each statement, see SQL statement data access classification for routines.

MODIFIES SQL DATA

Specifies that the procedure can execute any SQL statement except statements that are not supported in procedures.

MODIFIES SQL DATA is the default.

READS SQL DATA

Specifies that procedure can execute statements with a data access indication of READS SQL DATA or CONTAINS SQL. The procedure cannot execute SQL statements that modify data.

CONTAINS SQL

Specifies that the procedure can execute only SQL statements with an access indication of CONTAINS SQL. The procedure cannot execute statements that read or modify data.

CALLED ON NULL INPUT

Specifies that the procedure will be called if any, or even if all parameter values are null.

DYNAMIC RESULT SETS integer

Specifies the maximum number of query result sets that the procedure can return. The default is DYNAMIC RESULT SETS 0, which indicates that there are no result sets. The value must be between 0 and 32767.

ALLOW DEBUG MODE, DISALLOW DEBUG MODE, or DISABLE DEBUG MODE

Specifies whether the version of the procedure can be run in debugging mode. The default for a new version of a procedure is determined using the value of the CURRENT DEBUG MODE special register.

ALLOW DEBUG MODE

Specifies that this version of the procedure can be run in debugging mode. When this version of the procedure is invoked and debugging is attempted, a WLM environment must be available.

DISALLOW DEBUG MODE

Specifies that the version of the procedure cannot be run in debugging mode.

You can use a subsequent ALTER PROCEDURE statement to change this option to ALLOW DEBUG MODE.

DISABLE DEBUG MODE

Specifies that the version of the procedure can never be run in debugging mode.

The version of the procedure cannot be changed to specify ALLOW DEBUG MODE or DISALLOW DEBUG MODE after the version of the procedure has been created, replaced, or altered to use DISABLE DEBUG MODE. To change DEBUG MODE for a version of a procedure that specifies DISABLE DEBUG MODE, you must drop and re-create the version of the procedure using the option that you want.

When DISABLE DEBUG MODE is in effect, the WLM ENVIRONMENT FOR DEBUG MODE option is ignored.

PARAMETER CCSID

Indicates whether the encoding scheme for character or graphic string parameters is ASCII, EBCDIC, or UNICODE. The default encoding scheme is the value that is specified in the CCSID clauses of the parameter list or in the field DEF ENCODING SCHEME on installation panel DSNTIPF.

This clause provides a convenient way to specify the encoding scheme for character or graphic string parameters. If individual CCSID clauses are specified for individual parameters in addition to this PARAMETER CCSID clause, the value that is specified in all of the CCSID clauses must be the same value that is specified in this clause.

If the data type for a parameter is a user-defined distinct type that is defined as a character or graphic type string, the CCSID of the distinct type must be the same as the value that is specified in this clause.

This clause also specifies the encoding scheme that will be used for system-generated parameters of the routine.

QUALIFIER schema-name

Specifies the implicit qualifier that is used for unqualified object names that are referenced in the procedure body. See Unqualified alias, index, JAR file, sequence, table, trigger, and view names for information about how the default for this option is determined.

PACKAGE OWNER authorization-name

Specifies the owner of the package that is associated with the version of the procedure. The SQL authorization ID of the process is the default value.

This authorization ID must have the privileges required to execute the SQL statements that are contained in the body of the routine and must contain the necessary bind privileges. The value of the PACKAGE OWNER option is subject to translation when sent to a remote system.

If the privilege set lacks SYSADM or SYSCTRL authority, authorization-name must be the same as one of the authorization IDs of the process. If the privilege set includes SYSADM or SYSCTRL authority, authorization-name can be any authorization ID that contains the necessary bind privileges.

ASUTIME

Specifies the total amount of processor time, in CPU service units, that a single invocation of a procedure can run. The value is unrelated to the ASUTIME column of the resource limit specification table.

When you are debugging a procedure, setting a limit can be helpful in case the procedure gets caught in a loop. For information on service units, see z/OS MVS Initialization and Tuning Guide.

NO LIMIT

Specifies that there is no limit on the number of CPU service units that the procedure can run.

NO LIMIT is the default.

LIMIT integer

The limit on the number of CPU service units is a positive integer in the range of 1 to 2 147 483 647. If the procedure uses more service units than the specified value, DB2 cancels the procedure. The CPU cycles that are consumed by parallel tasks in a procedure do not contribute towards the specified ASUTIME LIMIT.

COMMIT ON RETURN NO or COMMIT ON RETURN YES

Indicates whether DB2 commits the transaction immediately on return from the procedure.

COMMIT ON RETURN NO

DB2 does not issue a commit when the procedure returns. NO is the default.

COMMIT ON RETURN YES,

DB2 issues a commit when the procedure returns if the following statements are true:

• The SQLCODE that is returned by the CALL statement is not negative.
• The procedure is not in a must-abort state.

The commit operation includes the work that is performed by the calling application process and by the procedure.

If the procedure returns result sets, the cursors that are associated with the result sets must have been defined as WITH HOLD to be usable after the commit.

INHERIT SPECIAL REGISTERS or DEFAULT SPECIAL REGISTERS

Specifies how special registers are set on entry to the routine.

INHERIT SPECIAL REGISTERS

Specifies that the values of special registers are inherited, according to the rules that are listed in the table for characteristics of special registers in a procedure in Special registers in a user-defined function or a stored procedure.

INHERIT SPECIAL REGISTERS is the default.

DEFAULT SPECIAL REGISTERS

Specifies that special registers are initialized to the default values, as indicated by the rules in the table for characteristics of special registers in a procedure in Special registers in a user-defined function or a stored procedure.

WLM ENVIRONMENT FOR DEBUG MODE name

Specifies the WLM (workload manager) application environment used by DB2 when debugging the procedure. The name of the WLM environment is an SQL identifier.

If you do not specify WLM ENVIRONMENT FOR DEBUG MODE, DB2 uses the default WLM-established stored procedure address space that is specified at installation time.

The WLM ENVIRONMENT FOR DEBUG MODE value is ignored when DISABLE DEBUG MODE is in effect.

To change the environment that DB2 uses for debugging this procedure, you must have the appropriate authority for the WLM application environment. For an example of a RACF command that provides this authorization, see Running stored procedures.

DEFER PREPARE or NODEFER PREPARE

Specifies whether to defer preparation of dynamic SQL statements that refer to remote objects, or to prepare them immediately.

The default depends on the value that is specified for the REOPT option. If REOPT NONE is specified, the default is NODEFER PREPARE. Otherwise, the default is DEFER PREPARE.

DEFER PREPARE

Specifies that the preparation of dynamic SQL statements that refer to remote objects will be deferred.

For considerations with distributed processing, see DEFER and NODEFER bind options.

NODEFER PREPARE

Specifies that the preparation of dynamic SQL statements that refer to remote objects will not be deferred.

CURRENT DATA

Specifies whether to require data currency for read-only and ambiguous cursors when the isolation level of cursor stability is in effect. CURRENT DATA also determines whether block fetch can be used for distributed, ambiguous cursors. For more information about updating the current row of a cursor, block fetch, and data currency, see DB2 Application Programming and SQL Guide.

YES

Specifies that data currency is required for read-only and ambiguous cursors. DB2 acquired page or row locks to ensure data currency. Block fetch is not allowed for distributed, ambiguous cursors.

NO

Specifies that data currency is not required for read-only and ambiguous cursors. Block fetch is allowed for distributed, ambiguous cursors. Use of CURRENT DATA(NO) is not recommended if the procedure attempts to dynamically prepare and execute a DELETE WHERE CURRENT OF statement against an ambiguous cursor after that cursor is opened. You receive a negative SQLCODE if your procedure attempts to use a DELETE WHERE CURRENT OF statement for any of the following cursors:

• A cursor that is using block fetch
• A cursor that is using query parallelism
• A cursor that is positioned on a row that is modified by this or another application process

No is the default.

DEGREE

Specifies whether to attempt to run a query using parallel processing to maximize performance.

1

Specifies that parallel processing should not be used.

1 is the default.

ANY

Specifies that parallel processing can be used.

CONCURRENT ACCESS RESOLUTION

Specifies the whether processing uses only committed data or whether it will wait for commit or rollback of data that is in the process of being updated.

WAIT FOR OUTCOME

Specifies that processing will wait for the commit or rollback of data that is in the process of being updated.

USE CURRENTLY COMMITTED

Specifies that processing use the currently committed version of the data when data that is in the process of being updated is encountered. USE CURRENTLY COMMITTED is applicable on scans that access tables that are defined in universal table spaces with row or page level lock size.

When there is lock contention between a read transaction and an insert transaction, USE CURRENTLY COMMITTED is applicable to scans with isolation level CS or RS. Applicable scans include intent read scans for read-only and ambiguous queries and for updatable cursors. USE CURRENTLY COMMITTED is also applicable to scans initiated from WHERE predicates of UPDATE or DELETE statements and the subselect of INSERT statements.

When there is lock contention is between a read transaction and a delete transaction, USE CURRENTLY COMMITTED is applicable to scans with isolation level CS and when CURRENT DATA NO is specified.

DYNAMICRULES

Specifies the values that apply, at run time, for the following dynamic SQL attributes:

• The authorization ID that is used to check authorization
• The qualifier that is used for unqualified objects
• The source for application programming options that DB2 uses to parse and semantically verify dynamic SQL statements

DYNAMICRULES also specifies whether dynamic SQL statements can include GRANT, REVOKE, ALTER, CREATE, DROP, and RENAME statements.

In addition to the value of the DYNAMICRULES clause, the run time environment of a native SQL procedure controls how dynamic SQL statements behave at run time. The combination of the DYNAMICRULES value and the run time environment determines the value for the dynamic SQL attributes. That set of attribute values is called the dynamic SQL statement behavior. The following values can be specified:

RUN

Specifies that dynamic SQL statements are to be processed using run behavior.

RUN is the default.

BIND

Specifies that dynamic SQL statements are to be processed using bind behavior.

DEFINEBIND

Specifies that dynamic SQL statements are to be processed using either define behavior or bind behavior.

DEFINERUN

Specifies that dynamic SQL statements are to be processed using either define behavior or run behavior.

INVOKEBIND

Specifies that dynamic SQL statements are to be processed using either invoke behavior or bind behavior.

INVOKERUN

Specifies that dynamic SQL statements are to be processed using either invoke behavior or run behavior.

See Authorization IDs and dynamic SQL for information on the effects of these options.

APPLICATION ENCODING SCHEME

Specifies the default encoding scheme for SQL variables in static SQL statements in the procedure body. The value is used for defining an SQL variable in a compound statement if the CCSID clause is not specified as part of the data type, and the PARAMETER CCSID routine option is not specified.

ASCII

Specifies that the data is encoded using the ASCII CCSIDs of the server.

EBCDIC

Specifies that the data is encoded using the EBCDIC CCSIDs of the server.

UNICODE

Specifies that the data is encoded using the Unicode CCSIDs of the server.

For information about how the default for this option is determined, see ENCODING bind option.

WITH EXPLAIN or WITHOUT EXPLAIN

Specifies whether information will be provided about how SQL statements in the procedure will execute.

WITHOUT EXPLAIN

Specifies that information will not be provided about how SQL statements in the procedure will execute.

You can get EXPLAIN output for a statement that is embedded in a native SQL procedure that is specified using WITHOUT EXPLAIN by embedding the SQL statement EXPLAIN in the procedure body. Otherwise, the value of the EXPLAIN option applies to all explainable SQL statements in the procedure body, and to the fullselect portion of any DECLARE CURSOR statements.

WITHOUT EXPLAIN is the default.

WITH EXPLAIN

Specifies that information will be provided about how SQL statements in the procedure will execute. Information is inserted into the table owner.PLAN_TABLE. owner is the authorization ID of the owner of the procedure package. Alternatively, the authorization ID of the owner of the procedure can have an alias as owner.PLAN_TABLE that points to the base table, PLAN_TABLE. owner must also have the appropriate SELECT and INSERT privileges on that table. WITH EXPLAIN does not obtain information for statements that access remote objects. PLAN_TABLE must have a base table and can have multiple aliases with the same table name, PLAN_TABLE, but have different schema qualifiers; it cannot be a view or a synonym. It should exist before the version is added or replaced. In all inserts to owner.PLAN_TABLE, the value of QUERYNO is the statement number that is assigned by DB2.

The WITH EXPLAIN option also populates two optional tables, if they exist: DSN_STATEMNT_TABLE and DSN_FUNCTION_TABLE. DSN_STATEMNT_TABLE contains an estimate of the processing cost for an SQL statement.

For a description of the tables that are populated by the WITH EXPLAIN option, see EXPLAIN.

WITH IMMEDIATE WRITE or WITHOUT IMMEDIATE WRITE

Specifies whether immediate writes are to be done for updates that are made to group buffer pool dependent page sets or partitions. This option is only applicable for data sharing environments. The IMMEDWRITE subsystem parameter has no affect of this option. IMMEDWRITE bind option shows the implied hierarchy of the IMMEDWRITE bind option (which is similar to this procedure option) as it affects run time.

WITHOUT IMMEDIATE WRITE

Specifies that normal write activity is performed. Updated pages that are group buffer pool dependent are written at or before phase one of commit or at the end of abort for transactions that have been rolled back.

WITHOUT IMMEDIATE WRITE is the default.

WITH IMMEDIATE WRITE

Specifies that updated pages that are group buffer pool dependent are immediately written as soon as the buffer update completes. Updated pages are written immediately even if the buffer is updated during forward progress or during the rollback of a transaction. WITH IMMEDIATE WRITE might impact performance.

ISOLATION LEVEL RR, RS, CS, or UR

Specifies how far to isolate the procedure from the effects of other running applications. For information about isolation levels, see Managing DB2 Performance.

RR

Specifies repeatable read.

RS

Specifies read stability.

CS

Specifies cursor stability. CS is the default.

UR

Specifies uncommitted read.

WITH KEEP DYNAMIC or WITHOUT KEEP DYNAMIC

Specifies whether DB2 keeps dynamic SQL statements after commit points.

WITHOUT KEEP DYNAMIC

Specifies that DB2 does not keep dynamic SQL statements after commit points.

WITHOUT KEEP DYNAMIC is the default.

WITH KEEP DYNAMIC

Specifies that DB2 keeps dynamic SQL statements after commit points. If you specify WITH KEEP DYNAMIC, the application does not need to prepare an SQL statement after every commit point. DB2 keeps the dynamic SQL statement until one of the following occurs:

• The application process ends
• A rollback operations occurs
• The application executes an explicit PREPARE statement with the same statement identifier as the dynamic SQL statement

If you specify WITH KEEP DYNAMIC, and the prepared statement cache is active, the DB2 subsystem keeps a copy of the prepared statement in the cache. If the prepared statement cache is not active, the subsystem keeps only the SQL statement string past a commit point. If the application executes an OPEN, EXECUTE, or DESCRIBE operation for that statement, the statement is implicitly prepared.

If you specify WITH KEEP DYNAMIC, DDF server threads that are used to execute procedures or packages that have this option in effect will remain active. Active DDF server threads are subject to idle thread time outs, as described in DB2 Installation Guide for installation panel DSNTIPR.

If you specify WITH KEEP DYNAMIC, you must not specify REOPT ALWAYS. WITH KEEP DYNAMIC and REOPT ALWAYS are mutually exclusive. However, you can specify WITH KEEP DYNAMIC and REOPT ONCE.

Use WITH KEEP DYNAMIC to improve performance if your DRDA client application uses a cursor that is defined as WITH HOLD. The DB2 subsystem automatically closes a held cursor when there are no more rows to retrieve, which eliminates an extra network message.

OPTHINT string-constant

Specifies whether query optimization hints are used for static SQL statements that are contained within the body of the procedure.

string-constantis a character string of up to 128 bytes in length, which is used by the DB2 subsystem when searching the PLAN_TABLE for rows to use as input. The default value is an empty string, which indicates that the DB2 subsystem does not use optimization hints for static SQL statements.

Optimization hints are only used if optimization hints are enabled for you system. See DB2 Installation Guide for information about enabling optimization hints.

SQL PATH

Specifies the SQL path that the DB2 subsystem uses to resolve unqualified user-defined types, functions, and procedure names (in CALL statements) in the body of the procedure. The default value is "SYSIBM", "SYSFUN", "SYSPROC", and the value of the QUALIFIER option.

The maximum length of the SQL path is 2048 bytes. DB2 calculates the length by taking each schema-name specified and removing any trailing blanks from it, adding two delimiters around it, and adding one comma after each schema name except for the last one. The length of the resulting string cannot exceed 2048 bytes.

schema-name

Specifies a schema. DB2 does not validate that the specified schema actually exists when the ALTER statement is processed.

schema-name-list

Specifies a comma separated list of schema names. The same schema name should not appear more than one time in the list of schema names. The number of schema names that you can specify is limited by the maximum length of the resulting SQL path.

SYSTEM PATH

Specifies the schema names "SYSIBM", "SYSFUN", "SYSPROC".

SESSION_USER or USER

Specifies the value of the SESSION_USER (or USER) special register. At the time the ALTER statement is processed, the actual length is included in the total length of the list of schema names that is specified for the PATH option. If you specify SESSION_USER (or USER) in a list of schema names, do not use delimiters around the SESSION_USER (or USER) keyword.

RELEASE AT

Specifies when to release resources that the procedure uses: either at each commit point or when the procedure terminates.

COMMIT

Specifies that resources will be released at each commit point.

COMMIT is the default.

DEALLOCATE

Specifies that resources will be released only when the procedure terminates. DEALLOCATE has no effect on packages that run on a DB2 server through a DRDA connection with a client system. DEALLOCATE also has no effect on dynamic SQL statements, which always use RELEASE AT COMMIT, with this exception: When you use the RELEASE AT DEALLOCATE clause and the WITH KEEP DYNAMIC clause, and the subsystem is installed with a value of YES for the field CACHE DYNAMIC SQL on installation panel DSNTIP8, the RELEASE AT DEALLOCATE option is honored for dynamic SELECT and SQL data change statements.

Locks that are acquired for dynamic statements are held unit one of the following events occurs:

• The application process ends.
• The application process issues a PREPARE statement with the same statement identifier. (Locks are released at the next commit point).
• The statement is removed from the prepared statement cache because the statement has not been used. (Locks are released at the next commit point).
• An object that the statement is dependent on is dropped or altered, or a privilege that the statement needs is revoked. (Locks are released at the next commit point).

RELEASE AT DEALLOCATE can increase the package size because additional items become resident in the package.

For more information about how the RELEASE clause affects locking and concurrency, see Managing DB2 Performance.

QUERY ACCELERATION

Specifies whether a static SQL query is bound for acceleration, and if so, with what behavior.

NONE

Specifies that no static SQL query in the application is bound for acceleration or will be accelerated when the application is run.

ENABLE

Specifies that a static SQL query is bound for acceleration if it satisfies the acceleration criteria, including the cost and heuristics criteria. The query is routed to an accelerator when the application runs. Otherwise, if the static query does not satisfy the acceleration criteria, the query is bound for execution in DB2.

If an error condition, such as one of the following examples, occurs while executing the accelerated static query when the application is run, DB2 fails the static query and returns a negative SQL code to the application:

• A failure occurs while running the static query on the accelerator.
• The accelerator returns an error for the query.
• The accelerator is not started and DB2 cannot route the static query to the accelerator for execution.

ENABLE WITH FAILBACK

Results in the same behavior as ENABLE, except if one of the error conditions occurs on the first OPEN of the accelerated static query when the application is run. In this case, instead of failing the static query and returning a negative SQL code to the application, DB2 performs a temporary statement-level incremental bind of the query and runs the query in DB2. The application does not see the acceleration failure. Failback to DB2 is not possible after the application does a successful OPEN for the query on the accelerator.

ELIGIBLE

Specifies that a static SQL query is bound for acceleration if the query meets the basic acceleration criteria, regardless of the cost or heuristics criteria. The query is routed to the accelerator when the application runs.

Like the behavior for ENABLE, if an error condition occurs while executing the accelerated static query when the application is run, DB2 fails the static query and returns a negative SQL code to the application.

ALL

Specifies that all of the static SQL queries in the application are to be bound for acceleration and routed to the accelerator when the application runs. If DB2 determines that a static query cannot be bound to run on the accelerator and the query references a user base table or view, the BIND or REBIND PACKAGE operation fails with an error message for that query. (A failure exception is made for declared global temporary tables (DGTTs) and created global temporary tables and (CGTTs) because these tables cannot be accelerated.)

Like the behavior for ENABLE, if an error condition occurs while executing the accelerated static query when the application is run, DB2 fails the static query and returns a negative SQL code to the application.

This bind option does not apply to a fullselect or WITH common-table-expression that is specified in a RETURN statement for the routine, or in a SET host-variable-assignment that is used in the routine. The queries that are specified in these cases cannot be accelerated.

GET_ACCEL_ARCHIVE

Specifies whether a static SQL query that is bound for acceleration retrieves archived data on the accelerator, instead of active data.

NO

Specifies that no static SQL query is bound to retrieve archived data from the accelerator. If the static query also is not bound for acceleration, the query is bound to run in DB2.

If the static query is bound for acceleration because the QUERYACCELERATION bind option was specified, the query is routed to the accelerator when the application runs; however, the query does not retrieve any archived data.

YES

Specifies that if all of the following criteria are met, the query is bound for acceleration and retrieves the archived data on the accelerator when the application runs:

• The QUERYACCELERATION bind option is also specified.
• The static SQL query references an accelerated table that has partitioned data archived on an accelerator.
• The static query satisfies the acceleration criteria that is specified by the QUERYACCELERATION bind option.

If the static query does not satisfy the acceleration criteria that is specified by the QUERYACCELERATION bind option, the BIND or REBIND PACKAGE operation fails with an error message for that query.

This bind option does not apply to a fullselect or WITH common-table-expression that is specified in a RETURN statement for the routine, or in a SET host-variable-assignment that is used in the routine. The queries that are specified in these cases cannot be accelerated.

REOPT

Specifies if DB2 will determine the access path at run time by using the values of SQL variables or SQL parameters, parameter markers, and special registers.

NONE

Specifies that DB2 does not determine the access path at run time by using the values of SQL variables or SQL parameters, parameter markers, and special registers.

NONE is the default.

ALWAYS

Specifies that DB2 always determine the access path at run time each time an SQL statement is run.

ONCE

Specifies that DB2 determine the access path for any dynamic SQL statements only one time, at the first time the statement is opened. This access path is used until the prepared statement is invalidated or removed from the dynamic statement cache and needs to be prepared again.

VALIDATE RUN or VALIDATE BIND

Specifies whether to recheck, at run time, errors of the type "OBJECT not FOUND" and NOT AUTHORIZED" that are found during bind or rebind. The option has no effect if all objects and needed privileges exist.

VALIDATE RUN

Specifies that if needed objects or privileges do not exist when the ALTER PROCEDURE statement is processed, warning messages are returned, but the ALTER PROCEDURE statement succeeds. The DB2 subsystem rechecks for the objects and privileges at run time for those SQL statements that failed the checks during processing of the ALTER PROCEDURE statement. The authorization checks the use of the authorization ID of the owner of the procedure package.

VALIDATE RUN is the default.

VALIDATE BIND

Specifies that if needed objects or privileges do not exist at the time the ALTER PROCEDURE statement is processed, an error is issued and the ALTER PROCEDURE statement fails.

ROUNDING

Specifies the rounding mode for manipulation of DECFLOAT data.

DEC_ROUND_CEILING

Specifies numbers are rounded towards positive infinity.

DEC_ROUND_DOWN

Specifies numbers are rounded towards 0 (truncation).

DEC_ROUND_FLOOR

Specifies numbers are rounded towards negative infinity.

DEC_ROUND_HALF_DOWN

Specifies numbers are rounded to nearest; if equidistant, round down.

DEC_ROUND_HALF_EVEN

Specifies numbers are rounded to nearest; if equidistant, round so that the final digit is even.

DEC_ROUND_HALF_UP

Specifies numbers are rounded to nearest; if equidistant, round up.

DEC_ROUND_UP

Specifies numbers are rounded away from 0.

DATE FORMAT ISO, EUR, USA, JIS, or LOCAL

Specifies the date format for result values that are string representations of date or time values. See String representations of datetime values for more information.

The default format is specified in the DATE FORMAT field of installation panel DSNTIP4 of the system where the procedure is defined. You cannot use the LOCAL option unless you have a date exit routine.

DECIMAL(15), DECIMAL(31), DECIMAL(15,s), or DECIMAL(31,s)

Specifies the maximum precision that is to be used for decimal arithmetic operations. See Arithmetic with two decimal operands for more information. The default format is specified in the DECIMAL ARITHMETIC field of installation panel DSNTIPF of the system where the procedure is defined. If the form pp.s is specified, s must be a number between 1 and 9. s represents the minimum scale that is to be used for division.

FOR UPDATE CLAUSE OPTIONAL or FOR UPDATE CLAUSE REQUIRED

Specifies whether the FOR UPDATE clause is required for a DECLARE CURSOR statement if the cursor is to be used to perform positioned updates.

FOR UPDATE CLAUSE REQUIRED

Specifies that a FOR UPDATE clause must be specified as part of the cursor definition if the cursor will be used to make positioned updates.

FOR UPDATE CLAUSE REQUIRED is the default.

FOR UPDATE CLAUSE OPTIONAL

Specifies that the FOR UPDATE clause does not need to be specified in order for a cursor to be used for positioned updates. The procedure body can include positioned UPDATE statements that update columns that the user is authorized to update.

If the resulting DBRM for the procedure is very large, you might need extra storage when you specify FOR UPDATE CLAUSE OPTIONAL.

The FOR UPDATE clause of the select-statement with no column list applies to static or dynamic SQL statements. You can specify the FOR UPDATE OF clause of the select-statement with a column list to restrict updates to only the columns that are named in the column list and to specify the acquisition of update locks.

TIME FORMAT ISO, EUR, USA, JIS, or LOCAL

Specifies the time format for result values that are string representations of date or time values. See String representations of datetime values for more information.

The default format is specified in the TIME FORMAT field of installation panel DSNTIP4 of the system where the procedure is defined. You cannot use the LOCAL option unless you have a date exit routine.

SQL-routine-body

Specifies the statements that define the body of the SQL procedure. For information on the SQL control statements that are supported in native SQL procedures, see SQL control statements for SQL routines. If an SQL-procedure-statement is the only statement in the procedure body, the statement must not end with a semicolon.

Notes

Considerations for altering a version of a procedure:

To alter a version of a procedure, the environment settings that are in effect when the ALTER PROCEDURE statement is issued must be the same as the environment settings that are in effect when the version of the procedure is first created using the CREATE PROCEDURE or ALTER PROCEDURE statements if one of the following options is specified:

• QUALIFIER
• PACKAGE OWNER
• WLM ENVIRONMENT FOR DEBUG MODE
• OPTHINT
• SQL PATH
• DECIMAL (if the value includes a comma

Changing to a native SQL procedure:

You cannot change an external SQL procedure to a native SQL procedure. You can drop the external SQL procedure that you want to change by using the DROP statement and create a native SQL procedure with a similar definition using the CREATE PROCEDURE statement. Alternatively, you can create a native SQL procedure using a different schema.

Identifier resolution

See SQL control statements for SQL routines for information on how names are resolved to columns, SQL variables, or SQL routines for native SQL procedures. Name resolution is unchanged for external SQL procedures.

If duplicate names are used for columns and SQL variables and parameters, qualify the duplicate names by using the table designator for columns, the procedure name for parameters, and the label name for SQL variables.

Characteristics of the package that is generated for a version of a procedure:

The package that is associated with a version of a procedure is named as follows:

• location is set to the value of the CURRENT SERVER special register
• collection-id (schema) for the package is the same as the schema qualifier of the procedure
• package-id is the same as the specific name of the procedure
• version-id is the same as the version identifier for the initial version of the procedure

The package is generated using the bind options that correspond to the implicitly or explicitly specified procedure options. See Table 1 for more information. In addition to the corresponding bind options, the package is generated using the following bind options:

• DBPROTOCAL(DRDA)
• FLAG(1)
• SQLERROR(NOPACKAGE)
• ENABLE(*)

Considerations for a procedure that is defined using a TABLE LIKE name AS LOCATOR clause:

If a procedure is defined with a table parameter (the TABLE LIKE name AS LOCATOR clause was specified in the CREATE PROCEDURE statement to indicate that one of the input parameters is a transition table), the procedure cannot be changed with an ALTER PROCERDURE statement if the change requires that the parameter list be specified. For example, to add or replace a version of a native SQL procedure, the procedure must be dropped and re-created.

Considerations for SQL processor programs:

SQL processor programs, such as SPUFI, the command line processor, and DSNTEP2, might not correctly parse SQL statements in the routine body that end with semicolons. These processor programs accept multiple SQL statements as input, with each statement separated with a terminator character. Processor programs that use a semicolon as the SQL statement terminator can truncate a CREATE FUNCTION statement with embedded semicolons and pass only a portion of it to DB2. Therefore, you might need to change the SQL terminator character for these processor programs. For information on changing the terminator character for SPUFI and DSNTEP2, see Setting the SQL terminator character in a SPUFI input data set and DSNTEP2 and DSNTEP4.

Correspondence of procedure options to BIND options

The following table lists options for CREATE PROCEDURE and ALTER PROCEDURE and the corresponding options for the bind commands. For more information about bind options, see BIND and REBIND options for packages and plans

Table 1. Correspondence of procedure options to bind options

CREATE PROCEDURE or ALTER PROCEDURE option	bind commands option
APPLICATION ENCODING SCHEME	ENCODING(ASCII) ENCODING(EBCDIC) ENCODING(UNICODE)
CURRENT DATA NO	CURRENTDATA(NO)
CURRENT DATA YES	CURRENTDATA(YES)
DEFER PREPARE	DEFER(PREPARE)
NODEFER PREPARE	NODEFER(PREPARE)
DEGREE	DEGREE(ANY) DEGREE(1)
DYNAMICRULES	DYNAMICRULES(RUN) DYNAMICRULES(BIND) DYNAMICRULES(DEFINEBIND) DYNAMICRULES(DEFINERUN) DYNAMICRULES(INVOKEBIND) DYNAMICRULES(INVOKERUN)
GET_ACCEL_ARCHIVE NO	GETACCELARCHIVE(NO)
GET_ACCEL_ARCHIVE YES	GETACCELARCHIVE(YES)
ISOLATION LEVEL	ISOLATION(RR) ISOLATION(RS) ISOLATION(CS) ISOLATION(UR)
OPTHINT	OPTHINT
PACKAGE OWNER	OWNER
QUALIFIER	QUALIFIER
QUERY ACCELERATION NONE	QUERYACCELERATION(NONE)
QUERY ACCELERATION ENABLE	QUERYACCELERATION(ENABLE)
QUERY ACCELERATION ENABLE WITH FAILBACK	QUERYACCELERATION(ENABLE WITH FAILBACK)
QUERY ACCELERATION ELIGIBLE	QUERYACCELERATION(ELIGIBLE)
QUERY ACCELERATION ALL	QUERYACCELERATION(ALL)
RELEASE AT COMMIT	RELEASE(COMMIT)
RELEASE AT DEALLOCATE	RELEASE(DEALLOCATE)
REOPT ALWAYS	REOPT(ALWAYS)
REOPT NONE	REOPT(NONE)
REOPT ONCE	REOPT(ONCE)
ROUNDING DEC_ROUND_CEILING	ROUNDING(CEILING)
ROUNDING DEC_ROUND_DOWN	ROUNDING(DOWN)
ROUNDING DEC_ROUNDING_FLOOR	ROUNDING(FLOOR)
ROUNDING DEC_ROUNDING_HALF_DOWN	ROUNDING(HALFDOWN)
ROUNDING DEC_ROUNDING_HALF_EVEN	ROUNDING(HALFEVEN)
ROUNDING DEC_ROUNDING_HALF_UP	ROUNDING(HALFUP)
ROUNDING DEC_ROUNDING_UP	ROUNDING(UP)
SQL PATH	PATH
VALIDATE BIND	VALIDATE(BIND)
VALIDATE RUN	VALIDATE(RUN)
WITH EXPLAIN	EXPLAIN(YES)
WITHOUT EXPLAIN	EXPLAIN(NO)
WITH IMMEDIATE WRITE	IMMEDWRITE(YES)
WITHOUT IMMEDIATE WRITE	IMMEDWRITE(NO)
WITH KEEPDYNAMIC	KEEPDYNAMIC(YES)
WITHOUT KEEPDYNAMIC	KEEPDYNAMIC(NO)

Invalidation of packages:

When a version of an SQL procedure is altered to change any option that is specified for the active version, all the packages that refer to that procedure are marked invalid. Additionally, when certain attributes of a native SQL procedure are changed, the body of the procedure might be rebound or regenerated. The following table summarizes when implicit rebind and regeneration occurs when specific options are changed. A value of Y in a row indicates that a rebind or regeneration occurs if the option is changed for a version of the procedure. A value of N in a row indicates that a rebind or regeneration does not occur.

Table 2. CREATE PROCEDURE and ALTER PROCEDURE options that result in rebind or regeneration when changed.

CREATE PROCEDURE or ALTER PROCEDURE option	Change requires rebind of invoking applications?	Change results in implicit rebind of the non-control statements of the body of the procedure?	Change results in implicit regeneration of the entire body of the procedure?
ALLOW DEBUG MODE, DISALLOW DEBUG MODE, or DISABLE DEBUG MODE	Y1, 2	Y1	Y
APPLICATION ENCODING SCHEME	Y	Y	Y
ASUTIME	Y	N	N
COMMIT ON RETURN	Y	N	N
CURRENT DATA	N	Y	N
DATE FORMAT	Y	Y	Y
DECIMAL	Y	Y	Y
DEFER PREPARE or NODEFER PREPARE	N	Y	N
DEGREE	N	Y	N
DYNAMIC RESULT SETS	Y	N	N
DYNAMICRULES	N	Y	N
FOR UPDATE CLAUSE OPTIONAL or FOR UPDATE CLAUSE REQUIRED	Y	Y	Y
INHERIT SPECIAL REGISTERS or DEFAULT SPECIAL REGISTERS	Y	N	N
ISOLATION LEVEL	N	Y	N
MODIFIES SQL DATA, READS SQL DATA, or CONTAINS SQL	Y	Y	Y
NOT DETERMINISTIC or DETERMINISTIC	N	N	N
OPTHINT	N	Y	N
PACKAGE OWNER	N	Y	N
QUALIFIER	N	Y	N
RELEASE AT COMMIT or RELEASE AT DEALLOCATE	N	Y	N
REOPT	N	Y	N
SQL PATH	N	Y	N
STOP AFTER SYSTEM DEFAULT FAILURES, STOP AFTER nn FAILURES, or CONTINUE AFTER FAILURES	Y	N	N
TIME FORMAT	Y	Y	Y
VALIDATE RUN or VALIDATE BIND	N	Y	N
WITH EXPLAIN or WITHOUT EXPLAIN	N	Y	N
WITH IMMEDIATE WRITE or WITHOUT IMMEDIATE WRITE	N	Y	N
WITH KEEP DYNAMIC or WITHOUT KEEP DYNAMIC	N	Y	N
WLM ENVIRONMENT FOR DEBUG MODE	Y	N	N
Note: The procedure package is rebound or regenerated if a value of ALLOW DEBUG MODE is changed to DISALLOW DEBUG MODE. Invoking applications are invalidated if a value of DISALLOW DEBUG MODE is changed to DISABLE DEBUG MODE.

Considerations for SYSENVIRONMENTS catalog table:

An ALTER statement that specifies a new environment settings will result in a new row being added to the SYSENVIRONMENTS catalog table. The new row will be added even if an error is subsequently encountered during processing of the ALTER statement. Thus, a new SYSENVIRONMENTS row might be added even for an ALTER statement that fails.

Compatibilities:

For compatibility with previous versions of DB2, when any of the following options are implicitly or explicitly specified as part of option-list, a warning is issued, but the statement is executed. However, if REPLACE or ADD VERSION is specified with one of the following options, an error is issued, and the statement does not execute. For example, if ADD VERSION and STAY RESIDENT are specified, an error is issued.

• STAY RESIDENT
• PROGRAM TYPE
• RUN OPTIONS
• NO DBINFO
• COLLID or NOCOLLID
• SECURITY
• PARAMETER STYLE GENERAL WITH NULLS
• STOP AFTER SYSTEM DEFAULT FAILURES
• STOP AFTER nn FAILURES
• CONTINUE AFTER FAILURES

If WLM ENVIRONMENT is specified for a native SQL procedure, WLM ENVIRONMENT FOR DEBUG MODE must be specified.

For compatibility with the CREATE PROCEDURE statement, the following clause can be specified, but will be ignored:

• LANGUAGE SQL

Alternative syntax and synonyms:

To provide compatibility with previous releases of DB2 or other products in the DB2 family, DB2 supports the following keywords:

• RESULT SET, RESULT SETS, and DYNAMIC RESULT SET as synonyms for DYNAMIC RESULT SETS.
• VARIANT as a synonym for NOT DETERMINISTIC
• NOT VARIANT as a synonym for DETERMINISTIC

Considerations for catalog comments for a routine definition:

When a function definition is replaced any existing comment in the catalog for the definition is removed, and when a function definition is regenerated any existing comment in the catalog for the definition is retained.

Example

ALTER PROCEDURE UPDATE_SALARY_1
      ALTER ACTIVE VERSION
      NOT DETERMINISTIC
      CALLED ON NULL INPUT
      ALLOW DEBUG MODE
      ASUTIME LIMIT 10

ALTER PROCEDURE UPDATE_SALARY_1
      REPLACE VERSION V2 (P1 INTEGER, P2 CHAR(5))
      MODIFIES SQL DATA
      UPDATE EMP SET SALARY = SALARY * RATE
            WHERE EMPNO = EMPLOYEE_NUMBER;

ALTER PROCEDURE UPDATE_SALARY_1
      ADD VERSION V3 (P1 INTEGER, P2 CHAR(5))
        UPDATE EMP SET SALARY = SALARY * (RATE*10)
            WHERE EMPNO = EMPLOYEE_NUMBER;

ALTER PROCEDURE UPDATE_SALARY_1
      ACTIVATE VERSION V3;

ALTER PROCEDURE UPDATE_SALARY_1
      REGENERATE ACTIVE VERSION;