What is the NVL function in Oracle?
What is the NVL function in Oracle?
NVL lets you replace null (returned as a blank) with a string in the results of a query. If expr1 is null, then NVL returns expr2 . If expr1 is not null, then NVL returns expr1 .
Can we use NVL for number in Oracle?
The Oracle NVL() function allows you to replace null with a more meaningful alternative in the results of a query. If the data type of e1 is numeric, Oracle determines which argument has the highest numeric precedence, implicitly converts the other argument to that data type, and returns that data type.
What is the full form of NVL in Oracle?
1 Answer. 1. As others have pointed out in comments, it probably stands for “null value” or “null value logic”. It might just as well be called “dflt” (or similar abbreviation) for “default”.
What is difference between NVL and coalesce?
NVL and COALESCE are used to achieve the same functionality of providing a default value in case the column returns a NULL. The differences are: NVL accepts only 2 arguments whereas COALESCE can take multiple arguments. NVL evaluates both the arguments and COALESCE stops at first occurrence of a non-Null value.
Can we use NVL in Join condition?
2 Answers. You can use a LEFT JOIN . That will return all rows from tableOne , and when it can’t find a match in the second table, it will return null. Then you can use NVL like you mentioned.
How do I use NVL in Oracle?
Another example using the NVL function in Oracle/PLSQL is: SELECT supplier_id, NVL(supplier_desc, supplier_name) FROM suppliers; This SQL statement would return the supplier_name field if the supplier_desc contained a null value. Otherwise, it would return the supplier_desc.
When to use the NVL function in Oracle?
This example use the NVL function to change a NULL to a blank space: The Oracle NULL Value (NVL) SQL operator is a great way to substitute NULL values with numeric values in Oracle SQL statements. The most common use for the NULL value (NVL) clause is to prevent mathematical operations from aborting with a zero divisor.
When to use implicit conversion in NVL-Oracle?
If expr1 is not null, then NVL returns expr1. The arguments expr1 and expr2 can have any datatype. If their datatypes are different, then Oracle Database implicitly converts one to the other. If they are cannot be converted implicitly, the database returns an error. The implicit conversion is implemented as follows:
How many arguments does the NVL ( ) function take?
The NVL () function accepts two arguments. If e1 evaluates to null, then NVL () function returns e2. If e1 evaluates to non-null, the NVL () function returns e1. The two arguments e1 and e2 can have the same or different data types.
How is the NVL function similar to the decode?
As you can see, the NVL function replaces a NULL with whatever value you desire. 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.