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Oracle pl/sql control statments
The PL/SQL IF/THEN statement checks a Boolean condition and executes statements in the THEN clause if true. It can check simple or complex expressions. There are single-level IF/THEN and multi-level IF/THEN/ELSE, IF/THEN/ELSIF/END IF, and nested IF statements to handle different outcomes. Operators like =, <>, <, > etc. are used to build conditional expressions.
Oracle pl/sql control statments
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- 2. PL/SQL IF/THEN/ELSE Statement TheIF/THEN statement checks a Boolean value or expression and if true, executes the statements in the THEN clause. If the condition is false, the statements in the THEN clause are skipped and execution jumps to the END IF, and the expression that is checked must return a true or false. It can be a simple Boolean variable or a compound expression joined with AND/OR clauses, and the expression can even be a PL/SQL function that returns a Boolean value. • IF...THEN • IF...THEN...ELSE • IF...THEN...ELSIF...ENDIF • IF…THEN…ELSIF…THEN…ELSE…END IF •
- 3. IF THEN statement •IF THEN...END IF statement is a single-level conditional statement which executes a sequence of statements based on a given condition. • Syntax: IF condition THEN executable statements END IF; • Condition Expression evaluates to TRUE or FALSE If TRUE commands execute
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- 6. IF THEN ELSEstatement • The IF-THEN-ELSE statement is next level of extension of above the IF-THEN statement, as it provides the ability to give direction for FALSE or NULL also. • Syntax: IF condition THEN executable statements 1 ELSE executable statements 2 END IF;
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- 8. IF THEN ELSIFENDIF statement • For multiple possible outcomes of a condition, we use the IF THEN ELSIF ENDIF statement • Syntax: IF condition1 THEN sequence_of_statements1 ELSIF condition2 THEN sequence_of_statements2 ELSE sequence_of_statements3 END IF;
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- 10. Nested IF statement •When using an ELSIF construct, it is not necessary to specify what action should be taken if none of the conditions evaluate to TRUE. In other words, an ELSE clause is not required in the ELSIF construct.