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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: TutorialThe HCL OneDB™ Guide to SQL: Tutorial shows how to use basic and advanced structured query language (SQL) to access and manipulate the data in your databases. It discusses the data manipulation language (DML) statements as well as triggers and stored procedure language (SPL) routines, which DML statements often use.
Programming for a multiuser environment
How locks workHCL® OneDB® database servers support a complex, flexible set of locking features that the topics in this section describe.
Lock scope
Table locks
Lock a table with the LOCK TABLE statement

Lock a table with the LOCK TABLE statement

A transaction tells the database server to use table-level locking for a table with the LOCK TABLE statement. The following example shows how to place an exclusive lock on a table:

LOCK TABLE tab1 IN EXCLUSIVE MODE

The following example shows how to place a shared lock on a table:

LOCK TABLE tab2 IN SHARE MODE

Tip: You can set the isolation level for your database server to achieve the same degree of protection as the shared table lock while providing greater concurrency.