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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.
Altering BYTE and TEXT columnsYou can use the MODIFY clause to change a BYTE column to a TEXT column, and vice versa. You can also use the MODIFY clause to change a BYTE column to a BLOB column and a TEXT column to a CLOB column.

Altering BYTE and TEXT Column data types

You can use the MODIFY clause to change a BYTE column to a TEXT column, and vice versa. You can also use the MODIFY clause to change a BYTE column to a BLOB column and a TEXT column to a CLOB column.

Except for these operations, however, you cannot use the MODIFY clause to change a BYTE or TEXT column to any other type of column, nor to change any other type of column to a BYTE or TEXT column.

When you use this clause to change a BYTE column to a BLOB column, or to change a TEXT column to a CLOB column, you can also use the PUT Clause of the ALTER TABLE statement to specify an sbspace and to define its characteristics for storing the BLOB or CLOB objects.