What does NVL2 do in Oracle?

Table of Contents

NVL2 lets you determine the value returned by a query based on whether a specified expression is null or not null. If expr1 is not null, then NVL2 returns expr2 . If expr1 is null, then NVL2 returns expr3 .

What is NVL NVL2?

Nvl(arg1,arg2) nvl is used for converting null values. In nvl if argument 1 is null then it returns argument 2 but argument 1 is not null it returns itself. In nvl2 (arg1,arg2,arg3) in nvl2 it converts any number into according to given number with null also .

How does decode work in Oracle SQL?

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.

What is the difference between NVL and NVL2 functions in Oracle?

What is the difference between nvl and nvl2? Answer: The nvl function only has two parameters while the nvl parameter has three arguments. The nvl2 like like combining an nvl with a decode because you can transform a value: NVL ( expr1 , expr2 ): If expr1 is null, then NVL returns expr2.

How can I remove multiple special characters from a string in Oracle?

If you want to replace multiple, you can use nested functions, which can get messy. REGEXP_REPLACE uses regular expressions to replace characters….In Oracle SQL, you have three options for replacing special characters:

Using the REPLACE function.
Using the REGEXP_REPLACE function.
Using the TRANSLATE function.

What is the difference between NVL and NVL2 and coalesce?

NVL : Converts null value to an actual value. NVL2 : If first expression is not null, return second expression. If first expression is null, return third expression. the first expression can have any data type.

Can NVL have 3 parameters?

The Oracle NVL2() function accepts three arguments.

How do I decode a value in SQL query?

The basic syntax for writing DECODE function in SQL is as follows: DECODE (expression , search_1, result_1[, search_2, result_2].,[,search_n,result_n] [, default]); The parameters used in the above mentioned syntax are: expression: expression argument is the value which is to be searched and compared with.

How do I use decode?

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. If a match is not found, then default is returned. If default is omitted, then Oracle returns null.

How can I remove last 3 characters from a string in Oracle?

Oracle / PLSQL: RTRIM Function

Description. The Oracle/PLSQL RTRIM function removes all specified characters from the right-hand side of a string.
Syntax. The syntax for the RTRIM function in Oracle/PLSQL is: RTRIM( string1 [, trim_string ] )
Returns. The RTRIM function returns a string value.
Note.
Applies To.
Example.

Why case is faster than decode?

From performance perspective, In Oracle decode and CASE does not make any difference. But in Exadata , Decode is faster than CASE. The Decode operation is done at storage Server level where the data is present BUT CASE is done at DB Instance level which receives data from DB storage Level.

What is the difference between NVL NVL2 and Nullif?

What is SQL decode?

Can we use NVL in decode?

The DECODE and NVL functions are really special. They can be used for date, number, and character datatypes. I have found these two functions to be great time-savers when writing logic using Oracle SQL.

What is Oracle/PLSQL nvl2?

The Oracle/PLSQL NVL2 function extends the functionality found in the NVL function. It lets you substitutes a value when a null value is encountered as well as when a non-null value is encountered. The string to test for a null value.

How do you use nvl2 function?

NVL2 (expr1, expr2, expr3) : The NVL2 function examines the first expression. If the first expression is not null, then the NVL2 function returns the second expression. If the first expression is null, then the third expression is returned i.e. If expr1 is not null, NVL2 returns expr2. If expr1 is null, NVL2 returns expr3.

What is the difference between coalesce () and NVL () function in MySQL?

The advantage of the COALESCE () function over the NVL () function is that the COALESCE function can take multiple alternate values. In simple words COALESCE () function returns the first non-null expression in the list. Output : NULLIF () : The NULLIF function compares two expressions. If they are equal, the function returns null.

What is NVL (expr1) in SQL?

NVL (expr1, expr2) : In SQL, NVL () converts a null value to an actual value. Data types that can be used are date, character and number. Data type must match with each other i.e. expr1 and expr2 must of same data type. Syntax –. NVL (expr1, expr2) expr1 is the source value or expression that may contain a null.