The syscasts system catalog table describes the casts in the database. It contains one row for each built-in cast, each implicit cast, and each explicit cast that a user defines. The syscasts table has the following columns.
Table 1. SYSCASTS table column descriptions
Column Type Explanation
owner CHAR(32) Owner of cast (user informix for built-in casts and user name for implicit and explicit casts)
argument_type SMALLINT Source data type on which the cast operates
argument_xid INTEGER Code for the source data type specified in the argument_type column
result_type SMALLINT Code for the data type returned by the cast
result_xid INTEGER Data type code of the data type named in the result_type column
routine_name VARCHAR(128) Function or procedure implementing the cast
routine_owner CHAR(32) Name of owner of the function or procedure specified in the routine_name column
class CHAR(1) Type of cast: E = Explicit cast I = Implicit cast S = Built-in cast

If routine_name and routine_owner have NULL values, this indicates that the cast is defined without a routine. This can occur if both of the data types specified in the argument_type and result_type columns have the same length and alignment, and are passed by reference, or passed by value.

A composite index on columns argument_type, argument_xid, result_type, and result_xid allows only unique values. A composite index on columns result_type and result_xid allows duplicate values.