Αποτελέσματα Αναζήτησης
29 Δεκ 2014 · Let's stick to a format model first. SQL> alter session set nls_date_format='dd/mm/yyyy hh24:mi:ss'; Session altered. Now, let's use TO_DATE to explicitly convert the string literal to date.
Oracle CASE expression allows you to add if-else logic to SQL statements without having to call a procedure. The CASE expression evaluates a list of conditions and returns one of the multiple possible results. You can use a CASE expression in any statement or clause that accepts a valid expression.
2 Ιουν 2023 · The CASE statement allows you to perform an IF-THEN-ELSE check within an SQL statement. It’s good for displaying a value in the SELECT query based on logic that you have defined. As the data for columns can vary from row to row, using a CASE SQL expression can help make your data more readable and useful to the user or to the application.
7 Δεκ 2023 · How to use CASE for IF-THEN logic in SQL SELECT. If you want to see the grade for each exam, select the case expression like a regular column: It’s a good idea to give the expression an alias. This is particularly important if the case is in a subquery.
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.
Oracle Database 23c extended CASE expressions in PL/SQL to support dangling predicates in simple CASE expression. These work like regular simple CASE expressions - you have a single selector. Each WHEN clause may contain a comparison condition and the right-hand side of the formula.
The SQL CASE Expression. The CASE expression goes through conditions and returns a value when the first condition is met (like an if-then-else statement). So, once a condition is true, it will stop reading and return the result. If no conditions are true, it returns the value in the ELSE clause.