When the syntax of embedded SQL statements is fully known at precompile time, the statements are referred to as static SQL. This is in contrast to dynamic SQL statements whose syntax is not known until run time.
| Note: | Static SQL is not supported in interpreted languages, such as REXX. |
The structure of an SQL statement must be completely specified in order for a statement to be considered static. For example, the names for the columns and tables referenced in a statement must be fully known at precompile time. The only information that can be specified at run time are values for any host variables referenced by the statement. However, host variable information, such as data types, must still be precompiled.
When a static SQL statement is prepared, an executable form of the statement is created and stored in the package in the database. The executable form can be constructed either at precompile time, or at a later bind time. In either case, preparation occurs before run time. The authorization of the person binding the application is used, and optimization is based upon database statistics and configuration parameters that may not be current when the application runs.