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SQL programmingYou can use the HCL OneDB™ implementation of the SQL language to develop applications for 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
Handle a deadlock

Handle a deadlock

A deadlock is a situation in which a pair of programs blocks the progress of each other. Each program has a lock on some object that the other program wants to access. A deadlock arises only when all programs concerned set their lock modes to wait for locks.

The HCL® OneDB® database server detects deadlocks immediately when they only involve data at a single network server. It prevents the deadlock from occurring by returning an error code (error -143 ISAM error: deadlock detected) to the second program to request a lock. The error code is the one the program receives if it sets its lock mode to not wait for locks. If your program receives an error code related to locks even after it sets lock mode to wait, you know the cause is an impending deadlock.