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SQL programmingYou can use the HCL OneDB™ implementation of the SQL language to develop applications for HCL OneDB™ database servers.
Guide to SQL: SyntaxThe HCL OneDB™ Guide to SQL: Syntax describes the syntax of the statements, data types, expressions, operators, and built-in functions of the HCL OneDB™ dialect of the SQL language.
SQL statementsThis chapter describes the syntax and semantics of SQL statements that are recognized by HCL OneDB™.
CREATE CAST statementUse the CREATE CAST statement to register a cast that converts data from one data type to another.
Explicit and Implicit CastsProcessing queries with multiple data types often requires casts that convert data from one data type to another.

Explicit and Implicit Casts

Processing queries with multiple data types often requires casts that convert data from one data type to another.

You can use the CREATE CAST statement to create the following kinds of casts:

Use the CREATE EXPLICIT CAST statement to define an explicit cast.
Use the CREATE IMPLICIT CAST statement to define an implicit cast.

The database server invokes built-in casts to convert from one built-in data type to another built-in type that is not directly substitutable. For example, the database server performs conversion of a character type such as CHAR to a numeric type such as INTEGER through a built-in cast.