Delete specific values from column with where condition?

Delete specific values from column with where condition?


Here, I want to delete values/data from specific one column with the WHERE condition. I don't want to delete the complete row. It is possible like--


UPDATE TABLE SET columnName = null WHERE YourCondition

OR

The general form for this would be an UPDATE statement:
UPDATE <table name>
SET
    ColumnA = <NULL, or '', or whatever else is suitable for the new value for the column>
WHERE
    ColumnA = <bad value> /* or any other search conditions */

Example:

 In following table, I want delete Address of student which id is 2.

Here we write query for that as follows:

UPDATE Student
SET
    Address = NULL
WHERE
    Id = 2;
and Result is as follows:



Popular posts from this blog

SQL Basic- SQL Syntax

Image
          SQL Syntax:            SQL Syntax Database Tables A database contains one or more tables. Each table is identified by a name (e.g. "Student" or "Product").  Tables contain records (rows) with data. Below is a selection from the " Student " table: StudentID             StudentName               Address                Country 1             Ajay               Noida                India 2             Ajeet               Bareilly                India 3             Shivam               Nagaland...
Read more

Type Declaration Instruction in C

Type Declaration Instruction This instruction is used to declare the type of variables being used in the program. Any variable used in the program must be declared before using it in any statement. The type declaration statement is written at the beginning of main( ) function. Ex.: int bas ; float rs, grosssal ; char name, code ; There are several subtle variations of the type declaration instruction. These are discussed below: While declaring the type of variable we can also initialize it as shown below. int i = 10, j = 25 ; float a = 1.5, b = 1.99 + 2.4 * 1.44 ; The order in which we define the variables is sometimes important sometimes not. For example, int i = 10, j = 25 ; is same as int j = 25, j = 10 ; However, float a = 1.5, b = a + 3.1 ; is alright, but float b = a + 3.1, a = 1.5 ;         is not. This is because here we are trying to use a even before defining it. The following statements would work int a, b, c, d ; a = b = ...
Read more

SQL Basic- SQL Commands

Image
          SQL Commands                       The SQL commands to interact with relational databases are: CREATE,  SELECT,  INSERT,  UPDATE,  DELETE and  DROP.               These commands can be classified into groups based on their nature:           DDL - Data Definition Language.            DML - Data Manipulation Language.            DCL - Data Control Language.
Read more