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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
Control data modification with access modes

Control data modification with access modes

HCL® OneDB® database servers support access modes. Access modes affect read and write concurrency for rows within transactions and are set with the SET TRANSACTION statement. You can use access modes to control data modification among shared files.

Transactions are read-write by default. If you specify that a transaction is read-only, that transaction cannot perform the following tasks:

Insert, delete, or update table rows
Create, alter, or drop any database object such as a schema, table, temporary table, index, or stored routine
Grant or revoke privileges
Update statistics
Rename columns or tables

Read-only access mode prohibits updates.

You can execute stored routines in a read-only transaction as long as the routine does not try to perform any restricted operations.

For information about how to use the SET TRANSACTION statement to specify an access mode, see the HCL OneDB Guide to SQL: Syntax.