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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.
REFERENCES Clause
Restrictions on Referential Constraints

Restrictions on Referential Constraints

You must have the References privilege to create a referential constraint.

When you use the REFERENCES clause, you must observe the following restrictions:

The referenced and referencing tables must be in the same database.
The referenced column (or set of columns when you use the multiple-column constraint format) must have a unique or primary-key constraint.
The data types of the referencing and referenced columns must be identical.
The only exceptions are that a referencing column must be an integer data type if the referenced column is a serial data type:
- For BIGSERIAL referenced columns, use BIGINT referencing columns.
- For SERIAL referenced columns, use INT referencing columns.
- For SERIAL8 referenced columns, use INT8 referencing columns.
You cannot place a constraint on any column of a RAW table.
You cannot place a referential constraint on a BYTE, TEXT, BLOB, or CLOB column.
When you use the single-column constraint format, you can reference only one column.
When you use the multiple-column constraint format, the maximum number of columns in the REFERENCES clause is 16, and the total length of the columns cannot exceed 390 bytes if the page size is 2 kilobytes. (The maximum length increases with the page size.)

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