Compound Statement

A compound statement or block logically groups a series of statements. Temporary tables and variables created in a compound statement are local only to that block and are destroyed when exiting the block.

Usage

SQL

[label :] BEGIN [[NOT] ATOMIC]
    statement*
[EXCEPTION ex
    statement*
]
END

When a block is expected by an IF, LOOP, WHILE, etc. a single statement is also accepted by the parser. Even though the block BEGIN/END is not expected, the statement will execute as if wrapped in a BEGIN/END pair.

Syntax

If NOT ATOMIC or no ATOMIC clause is specified, the block will be executed non-atomically;
If ATOMIC is specified the block must execute atomically. If a transaction is already associated with the thread, no additional action will be taken - savepoints and/or sub-transactions are not currently used;
Otherwise, a transaction will be associated with the execution of the block;
The label must not be the same as any other label used in statements containing this one.