Αποτελέσματα Αναζήτησης
1 Ιουν 2023 · Oracle DECODE Function with NULL Values. As I mentioned above, the Oracle DECODE function is an exception to other functions in how it handles NULL values. It treats a NULL expression and NULL search as equal (so NULL == NULL). So, this example will return 1: SELECT DECODE(NULL, NULL, 1, 0) FROM DUAL;
15 Μαρ 2012 · select decode(type_id, null, 'Unknown', type_id), name, count(*) from. (. select 'asdf' type_id, 'name1' name from dual union all. select 'asdf' type_id, 'name2' name from dual union all. select null type_id, 'name3' name from dual. ) test_table. group by type_id,name;
Oracle DECODE() function and NULL. NULL cannot be compared to anything even NULL. However, DECODE() function treats two null values are being equal. The following statement returns the string Equal: SELECT DECODE (NULL, NULL, 'Equal', 'Not equal') FROM dual; Code language: SQL (Structured Query Language) (sql)
Purpose. DECODE compares expr to each search value one by one. If expr is equal to a search, then Oracle Database returns the corresponding result. If no match is found, then Oracle returns default. If default is omitted, then Oracle returns null.
12 Οκτ 2022 · In order to use the sign function, we first need to map the "Low" range to negative numbers, the "Medium" range to 0, and the "High" range to positive numbers. This mapping can be done with this expression: floor((x - :low_th) / (:high_th - :low_th)) And now it's easy to write the final query:
The Oracle/PLSQL DECODE function has the functionality of an IF-THEN-ELSE statement. Syntax. The syntax for the DECODE function in Oracle/PLSQL is: DECODE( expression , search , result [, search , result]... [, default] ) Parameters or Arguments. expression. The value to compare.
The DECODE function is not specifically for handling null values, but it can be used in a similar way to the NVL function, as shown by the following example. SQL> SELECT id, DECODE(col1, NULL, 'ZERO', col1) AS output FROM null_test_tab ORDER BY id; ID OUTPUT ----- ----- 1 ONE 2 ZERO 3 ZERO 4 ZERO 4 rows selected. SQL> NVL2
