Control Statements

**Table 1** Conditional statements
No.	Oracle Database	GaussDB
1	IF THEN	Supported.
2	IF THEN ELSE	Supported.
3	IF THEN ELSIF	Supported.
4	simple CASE: CASE selector WHEN selector_value_1 THEN statements_1 WHEN selector_value_2 THEN statements_2 ... WHEN selector_value_n THEN statements_n [ ELSE else_statements END CASE;]	Supported.
5	searched CASE: CASE WHEN condition_1 THEN statements_1 WHEN condition_2 THEN statements_2 ... WHEN condition_n THEN statements_n [ ELSE else_statements END CASE;]	Supported.

**Table 2** LOOP statements
No.	Oracle Database	GaussDB
1	[ label ] LOOP statements END LOOP [ label ];	Supported.
2	EXIT;	Supported.
3	EXIT WHEN;	Supported.
4	CONTINUE;	Supported.
5	CONTINUE WHEN;	Supported.

**Table 3** FOR LOOP statements
No.	Oracle Database	GaussDB	Difference
1	[ label ] FOR index IN [ REVERSE ] lower_bound..upper_bound LOOP statements END LOOP [ label ];	Supported, with differences.	When the keyword REVERSE is used in GaussDB, the lower bound must be greater than or equal to the upper bound; otherwise, the loop body is not executed.
2	EXIT WHEN;	Supported.	-
3	CONTINUE WHEN;	Supported.	-