change column value in sql code example

Example 1: sql update query

--update query example
 UPDATE table_name
 SET column1 = value1, column2 = value2, ...
 WHERE condition;

Example 2: how to change the value of a table in sql

UPDATE employees 
SET 
    address = '1300 Carter St',
    city = 'San Jose',
    postalcode = 95125,
    region = 'CA'
WHERE
    employeeID = 3;

Example 3: sql update from select

UPDATE YourTable 
SET Col1 = OtherTable.Col1, 
    Col2 = OtherTable.Col2 
FROM (
    SELECT ID, Col1, Col2 
    FROM other_table) AS OtherTable
WHERE 
    OtherTable.ID = YourTable.ID

Example 4: sql update from select

UPDATE
    Table_A
SET
    Table_A.col1 = Table_B.col1,
    Table_A.col2 = Table_B.col2
FROM
    Some_Table AS Table_A
    INNER JOIN Other_Table AS Table_B
        ON Table_A.id = Table_B.id
WHERE
    Table_A.col3 = 'cool'

Example 5: sql change column in existing table

'This adds 'NOT NULL' to excisting column counting in the table mytable'
ALTER TABLE mytable ALTER COLUMN counting INT NOT NULL;

Example 6: alter table query sql server change column

ALTER TABLE table_name
  DROP COLUMN column_name;