HPL/SQL - Procedural SQL on Hadoop, NoSQL and RDBMS

This is an old revision of the document!

---

====== IF Statement ====== IF statement executes a set of statements depending on the value of a boolean expression. HPL/HQL supports multiple syntaxes for IF statement. ===== IF - THEN - ELSIF/ELSEIF - ELSE - END IF ===== Syntax: <code language=sql> IF boolean_expression THEN statements [ELSIF | ELSEIF THEN statements ...] [ELSE statements] END IF; </code> **Example:** <code language=sql> IF state = 'CA' THEN code := 1; ELSIF state = 'NY' THEN code := 2; ELSIF state = 'MA' THEN code := 3; ELSE code := 5; END IF; </code> **Compatibility:** Oracle, Teradata, IBM DB2, MySQL, PostgreSQL, Netezza. ===== IF - BEGIN - END - ELSE - BEGIN - END ===== Syntax: <code language=sql> IF boolean_expression single_statement | block [ELSE single_statement | block]; </code> **Example:** <code language=sql> IF state = 'CA' SET code = 1; ELSE SET code = 5; </code> <code language=sql> IF state = 'CA' BEGIN SET code = 1; SET type = 'A'; END ELSE BEGIN SET code = 5; SET type = 'B'; END </code> **Compatibility:** Microsoft SQL Server.