Explicitly declares a table or view definition in a program. For
tables named in a DECLARE TABLE statement, SQL does not check the
schema to compare the definition with the explicit declaration.
An explicit table declaration is useful to:
o Document the definition in the source code of the program
o Allow references to tables that do not exist when SQL
precompiles the program, including:
- Tables created in other modules of the program
- Tables created dynamically
o Improve precompiler performance because SQL does not need to
attach to the schema to retrieve the table definition
o Make it easier to check that the declaration correctly
corresponds to a host structure the program uses to hold
values from or for the table
o Declare only a subset of columns contained in the schema
definition of the table if the program needs to use only some
of the columns
Additional Information:
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