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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 NEXT SIZE clauseUse the MODIFY NEXT SIZE clause to change the size of the next extent.

MODIFY NEXT SIZE clause

Use the MODIFY NEXT SIZE clause to change the size of the next extent.

This syntax fragment is part of the ALTER TABLE statement.


Element	Description	Restrictions	Syntax
kilobytes	Length (in kilobytes) assigned here to the next extent for this table	Specification cannot be a variable, and (4(page size)) < kilobytes < (chunk size)	Expression

The minimum extent size is 4 times the disk-page size. For example, on a system with 2-kilobyte pages, the minimum length is 8 kilobytes. The maximum length is the chunk size. The following example specifies an extent size of 32 kilobytes:

ALTER TABLE customer MODIFY NEXT SIZE 32;

This clause cannot change the size of existing extents. You cannot change the size of existing extents without unloading all of the data.

To change the size of existing extents, you must unload all the data, drop the table, modify the first-extent and next-extent sizes in the CREATE TABLE definition in the database schema, re-create the table, and reload the data. For information about how to optimize extent sizes, see your HCL OneDB™ Performance Guide.