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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 FRAGMENT statementUse the ALTER FRAGMENT statement to change the distribution strategy or the storage location of an existing table or index. This statement is an extension to the ANSI/ISO standard for the SQL language.
INIT ClauseThe INIT clause of the ALTER FRAGMENT statement can define or modify the fragmentation strategy or the storage location of an existing table or an existing index.
FRAGMENT BY Clause for TablesUse the FRAGMENT BY option of the INIT clause of the ALTER FRAGMENT statement to fragment an existing nonfragmented table, or to convert one table fragmentation strategy to another.
Changing an Existing Fragmentation Strategy on a Table

Changing an Existing Fragmentation Strategy on a Table

You can redefine a fragmentation strategy on a table if you decide that your initial strategy does not fulfill your needs. When you alter a fragmentation strategy, the database server discards the existing fragmentation strategy and moves records to fragments as defined in the new fragmentation strategy.

The following example shows the statement that originally defined the fragmentation strategy on the table account and then shows an ALTER FRAGMENT statement that redefines the fragmentation strategy:

CREATE TABLE account (col1 INT, col2 INT) 
   FRAGMENT BY ROUND ROBIN IN dbsp1, dbsp2;
ALTER FRAGMENT ON TABLE account
   INIT FRAGMENT BY EXPRESSION 
   col1 < 0 IN dbsp1,
   col2 >= 0 IN dbsp2;

If an existing dbspace is full when you redefine a fragmentation strategy, you must not use it in the new fragmentation strategy.