Αποτελέσματα Αναζήτησης
25 Οκτ 2016 · Use this: CASE WHEN test IS NULL AND SUBSTR(('99999999' - Tst_Date),1,4) > 2009 THEN 'Medi'. WHEN test IS NULL AND SUBSTR(('99999999' - Tst_Date),1,4) < 2009 THEN 'hills'. ELSE test. END AS "Phy". answered Oct 25, 2016 at 3:03.
Learn how to use the Oracle CASE expression to add if-else logic to SQL statements without calling a procedure. See the syntax and examples of simple and searched CASE expressions for different scenarios.
Is there a "better" way to rewrite a SELECT clause where multiple columns use the same CASE WHEN conditions so that the conditions are only checked once? See the example below.
In a simple CASE expression, Oracle Database searches for the first WHEN ... THEN pair for which expr is equal to comparison_expr and returns return_expr. If none of the WHEN ... THEN pairs meet this condition, and an ELSE clause exists, then Oracle returns else_expr. Otherwise, Oracle returns null.
The syntax for the CASE statement in Oracle/PLSQL is: CASE [ expression ] WHEN condition_1 THEN result_1 WHEN condition_2 THEN result_2 ... WHEN condition_n THEN result_n ELSE result END Parameters or Arguments expression Optional. It is the value that you are comparing to the list of conditions.
The CASE statement chooses from a sequence of conditions, and executes a corresponding statement. The CASE statement evaluates a single expression and compares it against several potential values, or evaluates multiple Boolean expressions and chooses the first one that is TRUE. Syntax. searched_case_statement ::= [ <<label_name>> ]
A CASE expression evaluates a list of conditions and returns one of multiple possible result expressions. The result of a CASE expression is a single value whereas the result of a CASE statement is the execution of a sequence of statements.
