• Floating point compare fields cannot be referenced in INCLUDE or OMIT statements.
• Any selection can be performed with either an INCLUDE or an OMIT statement. INCLUDE and OMIT are mutually exclusive.
• If several relational conditions are joined with a combination of AND and OR logical operators, the AND statement is evaluated first. The order of evaluation can be changed by using parentheses inside the COND expression.
• If any changes are made to record formats by user exits E15 or E32, the INCLUDE or OMIT statement must apply to the newest formats.
• DFSORT issues a message and terminates if an INCLUDE or OMIT statement is specified for a tape work data set sort or conventional merge application.
• If SZERO is in effect, -0 compares as less than +0 when numeric fields and constants are used. If NOSZERO is in effect, -0 compares as equal to +0 when numeric fields and constants are used.

Table 1 shows how DFSORT reacts to the result of a relational condition comparison, depending on whether the statement is INCLUDE or OMIT and whether the relational condition is followed by an AND or an OR logical operator.

When writing complex statements, the table in Table 1 helps you get the result that you want.