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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™.
SET TRANSACTION statementUse the SET TRANSACTION statement to define the isolation level and to specify whether the access mode of a transaction is read-only or read-write.
Access Modes

Access Modes

Access modes affect read and write concurrency for rows within transactions. Use access modes to control data modification. SET TRANSACTION can specify that a transaction is read-only or read-write. By default, transactions are read-write. When you specify a read-only transaction, certain limitations apply. Read-only transactions cannot perform the following actions:

Insert, delete, or update rows of a table.
Create, alter, or drop any database object such as schemas, tables, temporary tables, indexes, or SPL routines.
Grant or revoke access privileges.
Update statistics.
Rename columns or tables.

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