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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.
ATTACH ClauseUse the ATTACH clause of the ALTER FRAGMENT ON TABLE statement to combine tables that have identical structures into a table with the same fragmentation strategy.
Effect of the ATTACH Clause
Round-Robin Distribution Scheme

Round-Robin Distribution Scheme

The following example combines nonfragmented tables pen_types and pen_makers into a single, fragmented table, pen_types. Table pen_types resides in dbspace dbsp1, and table pen_makers resides in dbspace dbsp2. Table structures are identical in each table.

ALTER FRAGMENT ON TABLE pen_types ATTACH pen_types, pen_makers;

After you execute the ATTACH clause, the database server fragments the table pen_types using a round-robin scheme into two dbspaces: the dbspace that contained pen_types and the dbspace that contained pen_makers. Table pen_makers is consumed and no longer exists; all rows that were in table pen_makers are now in table pen_types.