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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™.
SELECT statementUse the SELECT statement to retrieve values from a database or from an SPL or collection variable. A SELECT operation is called a query.
FROM ClauseThe FROM clause of the SELECT statement lists table objects from which to retrieve data.
The ONLY KeywordIf the FROM clause includes a permanent table that is a supertable within a typed table hierarchy, the query returns the qualifying rows from both the supertable and from its subtables by default, unless you specify the ONLY keyword.

The ONLY Keyword

If the FROM clause includes a permanent table that is a supertable within a typed table hierarchy, the query returns the qualifying rows from both the supertable and from its subtables by default, unless you specify the ONLY keyword.

For the SELECT statement to return rows from the supertable only, you must include the ONLY keyword immediately before the supertable name in the FROM clause, and you must enclose the identifier or synonym of the supertable within parentheses, as in this example:

SELECT * FROM ONLY(super_tab);

The data sources for this query do not include the subtables of super_tab.