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It can include any data form in the expr1 statement. That is, NVL2 returns expr2 if expr1 is not null. If the first expression is null, the third expression is returned. The NVL2 function returns the second expression if the first expression is not null. The NVL2 function evaluates the first expression (expr1, expr2, expr3). Oracle NVL2 function is replaced by Case Statement in SQL Server. NVL2 works similar to ISNULL() but instead of checking and replacing one pair, NVL2 can check and replace two pairs of such cases in a single statement. Select Vname,ISNULL (Costpkg,0), shopid FROM Vegetables Here, all the null values are replaced with 0 using ISNULL(). The Figure 1 table provides the details of vegetables and in the column cost per kg, it takes null values.Īfter applying the ISNULL to the table in Figure 1, the result is produced and provided in a table in Table 1. Select Vname,ISNULL(Costpkg,0),Shopid From Vegetables The second parameter is the value to be replaced if the result is true. The first parameter is the value, or an expression checked for null. ISNULL( Value /Expression, alternative value ) Not only zero, but NULL, empty, and void as well. NVL is a substitution function, which means it displays one value while another is NULL. It's just NVL, but thinking of it as a Null Value might help. NVL is not an acronym for anything, unlike a lot of programming/database terminology. You only used NVL in Oracle it is not available in MySQL or SQL Server. It's important to grasp the difference between a NULL value and a zero value or a field of spaces. A field with a NULL value is the same as one that has no value. In a table, a NULL value is a value in a field that appears to be empty. The word NULL is used to describe a missing value in SQL. When an expression is checked with ISNULL, it will return an alternative value if it is true. When the value to be checked is null, it returns an alternative value if it is true. ISNULL checks whether the value or an expression is true or false. When an expression in SQL server is NULL, the ISNULL function allows you to return an alternative value for the null. ISNULL replaced the Oracle NVL function in the SQL server.