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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™.
DATABASE statementUse the DATABASE statement to open an accessible database as the current database. This statement is an extension to the ANSI/ISO standard for SQL.
EXCLUSIVE keywordThe EXCLUSIVE keyword opens the database in exclusive mode and prevents access by anyone but the current user. To allow others to access the database, you must first execute the CLOSE DATABASE statement and then reopen the database without the EXCLUSIVE keyword.

EXCLUSIVE keyword

The EXCLUSIVE keyword opens the database in exclusive mode and prevents access by anyone but the current user. To allow others to access the database, you must first execute the CLOSE DATABASE statement and then reopen the database without the EXCLUSIVE keyword.

The following statement opens the stores_demo database on the training database server in exclusive mode:

DATABASE stores_demo@training EXCLUSIVE;

If another user has already opened the specified database, exclusive access is denied, an error is returned, and no database is opened.

If you encounter this error, but you are unable to confirm that other users are connected to the database, your non-exclusive access might be caused by a sensor or task that is running in the Scheduler API. To temporarily disable the Scheduler, you can issue this SQL administration API command:

EXECUTE FUNCTION admin('scheduler shutdown');

After the admin('scheduler shutdown') routine has completed execution. retry the DATABASE ... EXCLUSIVE statement.

For more information on the Scheduler API commands, see your HCL OneDB™ Administrator's Guide. For information about the privileges that you must hold to call SQL administration API functions, see your HCL OneDB Administrator's Reference.