DB2 10.5 for Linux, UNIX, and Windows

SYSSTAT.COLUMNS catalog view

Each row represents a column defined for a table, view, or nickname.

Table 1. SYSSTAT.COLUMNS Catalog View
Column Name Data Type Nullable Updatable Description
TABSCHEMA VARCHAR (128)     Schema name of the table, view, or nickname that contains the column.
TABNAME VARCHAR (128)     Unqualified name of the table, view, or nickname that contains the column.
COLNAME VARCHAR (128)     Name of the column.
COLCARD BIGINT   Y Number of distinct values in the column; -1 if statistics are not collected; -2 for inherited columns and columns of hierarchy tables.
HIGH2KEY1 VARCHAR (254) Y Y Second-highest data value. Representation of numeric data changed to character literals. Empty if statistics are not collected. Empty for inherited columns and columns of hierarchy tables.
LOW2KEY1 VARCHAR (254) Y Y Second-lowest data value. Representation of numeric data changed to character literals. Empty if statistics are not collected. Empty for inherited columns and columns of hierarchy tables.
AVGCOLLEN INTEGER   Y Average space in bytes when the column is stored in database memory or a temporary table. For LOB data types that are not inlined, LONG data types, and XML documents, the value used to calculate the average column length is the length of the data descriptor. An extra byte is required if the column is nullable; -1 if statistics have not been collected; -2 for inherited columns and columns of hierarchy tables. Note: The average space required to store the column on disk may be different than the value represented by this statistic.
NUMNULLS BIGINT   Y Number of null values in the column; -1 if statistics are not collected.
PCTINLINED SMALLINT     Percentage of inlined data for columns with VARCHAR, VARGRAPHIC, LOB, or XML data types. -1 if statistics have not been collected or the column data type does not support storing data outside the row. Also -1 for VARCHAR and VARGRAPHIC column if the table is organized by column or the table is organized by row and the row size of the table does not exceed the maximum record length for the page size of the table space.
SUB_COUNT SMALLINT   Y Average number of sub-elements in the column. Applicable to character string columns only.
SUB_DELIM_LENGTH SMALLINT   Y Average length of the delimiters that separate each sub-element in the column. Applicable to character string columns only.
PCTENCODED SMALLINT   Y Percentage of values that are encoded as a result of compression for a column in a column-organized table; -1 if the table is not organized by column or if statistics are not collected; -2 for inherited columns and columns of hierarchy tables.
AVGCOLLENCHAR INTEGER   Y Average number of characters (based on the collation in effect for the column) required for the column; -1 if the data type of the column is long, LOB, or XML or if statistics have not been collected; -2 for inherited columns and columns of hierarchy tables.
Note:
  1. In the catalog view, the values of HIGH2KEY and LOW2KEY are always shown in the database code page and can contain substitution characters. However, the statistics are gathered internally in the code page of the column's table, and will therefore use actual column values when applied during query optimization.