SQL92 CAST Function

The CAST function defined in SQL92 is equivalent to the CONVERT function defined in ODBC. The syntax of the equivalent functions is as follows:

{ fn CONVERT (value-exp, data-type)} /* ODBC
CAST (value-exp AS data-type) /* SQL92

The SQL92 CAST function mandates which data types can be converted to which other data types. (For more information, see the SQL92 specification.) The CAST function is supported at the FIPS Transitional level.

An application can determine support for the CAST function as follows:

1. Call SQLGetInfo with the SQL_SQL_CONFORMANCE information type. If the return value for the information type is SQL_SC_FIPS127_2_TRANSITIONAL, SQL_SC_SQL92_INTERMEDIATE, or SQL_SC_SQL92_FULL, then the CAST function is supported.
   
   
2. If the return value of the SQL_SQL_CONFORMANCE information type is SQL_SC_ENTRY_LEVEL or 0, then call SQLGetInfo with the SQL_SQL92_VALUE_EXPRESSIONS information type. If the SQL_SVE_CAST bit is set, then the CAST function is supported.