What is decode in SQL query?
Introduction to SQL DECODE() DECODE function in Standard Query Language (SQL) is used to add procedural IF – THEN – ELSE like statements to a query. It compares a given expression with each search value one by one and returns a result on the basis of outcomes received from the comparison.
What is decode in SQL with example?
The DECODE function returns a value that is the same datatype as the first result in the list. If the first result is NULL, then the return value is converted to VARCHAR2. If the first result has a datatype of CHAR, then the return value is converted to VARCHAR2. If no matches are found, the default value is returned.
Can we use decode in SQL Server?
In Oracle, you can use DECODE function to evaluate a list of expressions, and if a value is matched return the corresponding result. In SQL Server, you can use CASE expression that is also supported by Oracle. Note that NULL values in DECODE function and CASE expression are handled differently .
What is decode and case in SQL?
DECODE performs an equality check only. CASE is capable of other logical comparisons such as < > etc. It takes some complex coding – forcing ranges of data into discrete form – to achieve the same effect with DECODE.
Why decode is used in SQL?
What is DECODE function in SQL? In Oracle, DECODE function allows us to add procedural if-then-else logic to the query. DECODE compares the expression to each search value one by one. If expression is equal to a search, then the corresponding result is returned by the Oracle Database.
Which is better decode or case in Oracle?
CASE is better than DECODE because it is easier to read, and can handle more complicated logic. As far as performance goes, there is minimal difference between CASE and DECODE, so it should not be a factor in your decisions.
What is DECODE function used for?
DECODE function in Standard Query Language (SQL) is used to add procedural IF – THEN – ELSE like statements to a query. It compares a given expression with each search value one by one and returns a result on the basis of outcomes received from the comparison. A decode function basically performs the task of CASE statements.
What is like function in SQL?
The SQL LIKE condition allows you to use wildcards to perform pattern matching in a query. The LIKE condition is used in the WHERE clause of a SELECT, INSERT, UPDATE, or DELETE statement.
How do you find a string in SQL?
How to Find a String within a String in SQL Server. In SQL Server, you can use the T-SQL CHARINDEX() function or the PATINDEX() function to find a string within another string.
Where is function SQL?
The SQL WHERE clause is used to filter the results and apply conditions in a SELECT, INSERT, UPDATE, or DELETE statement.
What is decode SQL w3schools?
DECODE is an advanced function that the Oracle database supports. It is used to work as an IF-THEN-ELSE statement. The DECODE function is supported in the various versions of the Oracle/PLSQL, including, Oracle 12c, Oracle 11g, Oracle 10g and Oracle 9i.
Does decode work in SQL Server?
What is difference between Case and decode?
CASE is a statement while DECODE is a function. CASE can work with logical operators other than ‘=’ : DECODE performs an equality check only. CASE is capable of other logical comparisons such as < ,> ,BETWEEN , LIKE etc.
Can we use decode inside decode?
It is possible to use DECODE, but you’d have to use nested DECODEs and you’d end up with something that’s much harder to read, understand and therefore maintain.
What is case and decode in SQL?
DECODE can check equality operators only where as CASE can support all relational operators DECODE can be used in sql only where as CASE can be used in SQL AND PL/SQL CASE is better than DECODE.
What is the difference between decode and case?
What is the equivalent of Decode in SQL Server?
In SQL Server the equivalent code is CASE statement. Here are the examples regarding how DECODE can be written in SQL Server.
What is difference between Case and decode in Oracle?
3. CASE can work as a PL/SQL construct. DECODE can work as a function inside SQL only. CASE can be an efficient substitute for IF-THEN-ELSE in PL/SQL.
How does The DECODE function in SQL work?
If there are no matches, the DECODE function will return default and if default is omitted, then the function will return NULL. The DECODE function will compare each bank_id value, one by one. DECODE function to compare two dates (date1 and date2), where, if date1 > date2, the DECODE function should return date2.
How to decode two arguments in SQL query?
It works like the following statement: If you want to specify the value when the first argument is not equal to the second one, you use the following form of the DECODE () function: It works like the following IF-THEN-ELSE statement: IF 1 = 2 THEN RETURN ‘Equal’; ELSE RETURN ‘Not Equal’; END IF ;
How to decode an expression in PL / SQL?
The syntax of the DECODE function in the PL/ SQL Oracle database is as shown in the below description – DECODE (expression/value, search expression 1, return value 1 [, search expression 2, return value 2], …. [, search expression n, return value n] [, default value])
How to decode 1, 2, not equal in SQL?
SELECT DECODE ( 1, 2, ‘Equal’ ); It works like the following statement: IF 1 = 2 THEN RETURN ‘Equal’; END IF ; If you want to specify the value when the first argument is not equal to the second one, you use the following form of the DECODE () function: SELECT DECODE ( 1, 2, ‘Equal’, ‘Not Equal’ );