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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.
Combining Nonfragmented Tables to Create a Fragmented Table

Combining Nonfragmented Tables to Create a Fragmented Table

When you transform tables with identical table structures into fragments into a single table, you allow the database server to manage the fragmentation instead of allowing the application to manage the fragmentation. The distribution scheme can be round-robin or expression based.

To make a single, fragmented table from two or more identically-structured, nonfragmented tables, the ATTACH clause must include the surviving table in the attach list. The attach list is the specified list of tables in the ATTACH clause.

To include a rowid column in the newly-created single, fragmented table, attach all tables first and then add the rowid with the ALTER TABLE statement.