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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.
Using the BEFORE, AFTER, and REMAINDER options

Using the BEFORE, AFTER, and REMAINDER options

The BEFORE and AFTER options allow you to place a new fragment either before or after an existing fragment. You cannot use the BEFORE and AFTER options when the distribution scheme is round-robin or range interval..

When you attach a new list or expression fragment without specifying an explicit BEFORE or AFTER keyword option, the database server places the added fragment at the end of the fragment list, unless a remainder fragment exists. If a remainder fragment exists, the new fragment, by default, is placed just before the remainder fragment. You cannot attach a new fragment after the remainder fragment.

You cannot define a remainder fragment when the distribution scheme is round-robin or range interval.

If you omit the AS PARTITION fragment specification, the default name of the fragment is the name of the dbspace where it is stored. If another fragment of the same table already has the same name as the dbspace, the database server issues an exception, and the ALTER FRAGMENT ATTACH operation fails.