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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™.
ALTER TABLE statementUse the ALTER TABLE statement to modify the schema of an existing table.
MODIFY Clause Use the MODIFY clause to change the data type, length, or default value of a column, to add or remove the security label of a column, to allow or disallow NULL values in a column, or to reset the serial counter of a SERIAL, SERIAL8, or BIGSERIAL column.
How Modifying a Column Affects Triggers

How Modifying a Column Affects Triggers

If you modify a column that appears in the triggering column list of an UPDATE trigger, the trigger is unchanged.

When you modify a column in a table, the triggers based on that table remain unchanged, but the column modification might invalidate the trigger.

The following statements illustrate the possible affects on triggers:

CREATE TABLE tab1 (i1 INT, i2 INT, i3 INT);
CREATE TABLE tab2 (i4 INT, i5 INT);
CREATE TRIGGER col1trig UPDATE OF i2 ON tab1 
   BEFORE(INSERT INTO tab2 VALUES(1,1)); 
ALTER TABLE tab2 MODIFY i4 CHAR;

After the ALTER TABLE statement, column i4 accepts only character values. Because character columns accept only values enclosed in quotation marks, the action clause of the col1trig trigger is invalidated.

If a trigger is invalidated when you modify the underlying table, drop and then re-create the trigger.