INSERT SELECT into existing table

Question: How can I INSERT  into an existing  table  using a SELECT statement from an existing table?

I don’t want to create  a new table , just simply INSERT  into an existing table

Answer:   To INSERT data  from an existing table into an existing table use the INSERT INTO  .. SELECT method. This method will  take a recordset from an existing  table and inserts into another existing table.

INSERT INTO myTable(col1,col2)

SELECT col1,col2 FROM myTableexisting

A common misunderstanding is to use the following pattern, which creates a new table.

SELECT * INTo myNewTable FROM myOLDTable

USE SQL_TOOLS
go
CREATE TABLE myTest 
(myID INT,
myvalue VARCHAR(100)
)
CREATE TABLE myTest2 
(myID INT,
myvalue VARCHAR(100)
)

GO
--insert source data into source table
INSERT INTO myTest
SELECT 1,'myvalue1'
UNION
SELECT 2, 'myalue2'
GO
--copy source data into a another table
INSERT INTO myTest2 (myID,myValue)
SELECT myID,myValue FROM myTest WHERE myID = 1

SELECT * FROM myTest2

DROP TABLE myTest
DROP TABLE myTest2

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