What is the meaning of NVL?

NVL

What is the purpose of Oracle NVL function show an example where you use it?

In Oracle, the NVL function allows you to replace a NULL value with another value. It’s helpful when you want to store the fact that there is no data for a particular column, but you want to display something else. I’ll show you a few examples of this.

How do I use NVL in MS SQL?

In Oracle, NVL(exp1, exp2) function accepts 2 expressions (parameters), and returns the first expression if it is not NULL, otherwise NVL returns the second expression. In SQL Server, you can use ISNULL(exp1, exp2) function.

Can group functions be used in where clause?

Group functions cannot be used in WHERE clause. The can appear in SELECT, HAVING and ORDER BY clause.

Can NVL be used in where clause?

where P_INFO, P_DATE and P_ID are parameters. In the normal case every parameter is NULL. But then the where clause AND msg_id = NVL(P_ID, msg_ID) don’t return the rows where msg_id itself is NULL.

How Tkprof will help to increase the performance?

The SORT value causes TKPROF to sort the SQL statements in order of the sum of the CPU time spent executing and the CPU time spent fetching rows before writing them to the output file. For greatest efficiency, always use SORT parameters.

What is NVL in MySQL?

In Oracle, the NVL function allows you to replace NULL with the specified expression i.e. it returns the first operand if it is not NULL, otherwise it returns the second operand. In MySQL you have to use IFNULL function.

How Isnull function works in SQL Server?

The SQL Server ISNULL function returns the replacement value if the first parameter expression evaluates to NULL. SQL Server converts the data type of replacement to data type of expression.

How do you make a cursor?

To use cursors in SQL procedures, you need to do the following:

1. Declare a cursor that defines a result set.
2. Open the cursor to establish the result set.
3. Fetch the data into local variables as needed from the cursor, one row at a time.
4. Close the cursor when done.

Which functions can be used as the group functions?

The types of group functions (also called aggregate functions) are:

• AVG, that calculates the average of the specified columns in a set of rows,
• COUNT, calculating the number of rows in a set.
• MAX, calculating the maximum,
• MIN, calculating the minimum,
• STDDEV, calculating the standard deviation,
• SUM, calculating the sum,

How do you use group functions?

Example of How to Group in Excel

1. Select the rows you wish to add grouping to (entire rows, not just individual cells)
2. Go to the Data Ribbon.
3. Select Group.
4. Select Group again.