What is NVL function in MySQL?
The NVL( ) function is available in Oracle, and not in MySQL or SQL Server. This function is used to replace NULL value with another value. It is similar to the IFNULL Function in MySQL and the ISNULL Function in SQL Server.
What is the use of NVL function with an example?
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.
What does NVL stand for?
NVL
| Acronym | Definition |
|---|---|
| NVL | National Veterinary Laboratory |
| NVL | Night Vision Laboratory (Night Vision and Electronic Sensors Directorate, NVESD; US Army) |
| NVL | Navy Virtual Library |
| NVL | New Venture Lab |
Why is the difference between NVL and nvl2 functions in SQL?
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 does decode work in SQL?
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.
What is NVL and nvl2 in SQL?
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 .
What is the difference between decode and case?
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. -1 for “…and can not use the DECODE in the where clause.” DECODE is a function and every function has a return value.
What is Trunc in SQL?
The TRUNC function replaces the value of its first argument with another value that has a smaller precision or the same precision. The TRUNCATE statement deletes all of the rows from a database table, without dropping the table schema.
How do I filter null in SQL?
How to Test for NULL Values?
- SELECT column_names. FROM table_name. WHERE column_name IS NULL;
- SELECT column_names. FROM table_name. WHERE column_name IS NOT NULL;
- Example. SELECT CustomerName, ContactName, Address. FROM Customers. WHERE Address IS NULL;
- Example. SELECT CustomerName, ContactName, Address. FROM Customers.
How do I select data without null values in SQL?
Below is the syntax to filter the rows without a null value in a specified column. Syntax: SELECT * FROM WHERE IS NOT NULL; Example: SELECT * FROM demo_orders WHERE ORDER_DATE IS NOT NULL; –Will output the rows consisting of non null order_date values.