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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 TABLE statementUse the CREATE TABLE statement to create a new permanent table in the current database.
Column definitionUse the column definition segment of the CREATE TABLE statement to declare the name and data type (and optionally the default value and the constraints or the security label) of a single column of the new table.
Single-Column Constraint FormatUse the Single-Column Constraint format to define and declare the name of at least one constraint on a single column, and to specify the mode of each constraint.
CHECK Clause

CHECK Clause

Use the CHECK clause to designate conditions that must be met before data can be assigned to a column during an INSERT or UPDATE statement.

This syntax fragment is part of the Single-Column Constraint Format and the Multiple-Column Constraint Format.

CHECK Clause

Notes:

¹ See Condition

The condition cannot include a user-defined routine.

During an insert or update, if the check constraint of a row evaluates to false, the database server returns an error. The database server does not return an error if a row evaluates to NULL for a check constraint. In some cases, you might want to use both a check constraint and a NOT NULL constraint.