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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
Set the lock mode
Not waiting for locks

Not waiting for locks

The disadvantage of waiting for locks is that the wait might become long (although properly designed applications should hold their locks briefly). When the possibility of a long delay is not acceptable, a program can execute the following statement:

SET LOCK MODE TO NOT WAIT

When the program requests a locked row, it immediately receives an error code (for example, error -107 Record is locked), and the current SQL statement terminates. The program must roll back its current transaction and try again.

The initial setting is not waiting when a program starts up. If you are using SQL interactively and see an error related to locking, set the lock mode to wait. If you are writing a program, consider making that one of the first embedded SQL statements that the program executes.