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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
What Happens with the Distribution Scheme?

What Happens with the Distribution Scheme?

You can attach a nonfragmented table to a table with any type of supported distribution scheme. In general, the resulting table has the same fragmentation strategy as the prior fragmentation strategy of the surviving table.

When you attach two or more nonfragmented tables, however, the distribution scheme can either be based on expression or round-robin.

Only the following distribution schemes can result from combining the distribution schemes of the tables in the ATTACH clause.


Prior Distribution Scheme of Surviving Table	Prior Distribution Scheme of Consumed Table	Resulting Distribution Scheme
None	None	Round-robin or expression
Round-robin	None	Round-robin
Expression	None	Expression