The SQL SELECT INTO statement can be used to create backup
copies of tables.
The SQL SELECT INTO
Statement
The SELECT INTO statement selects data from one table and inserts
it into a different table.
The SELECT INTO statement is most often used to create backup copies
of tables.
SQL SELECT INTO Syntax
We can select all columns into the new table:
SELECT *
INTO new_table_name [IN externaldatabase]
FROM old_tablename
INTO new_table_name [IN externaldatabase]
FROM old_tablename
Or we can select only the columns we want into the new table:
SELECT column_name(s)
INTO new_table_name [IN externaldatabase]
FROM old_tablename
INTO new_table_name [IN externaldatabase]
FROM old_tablename
SQL SELECT INTO Example
Make a Backup Copy - Now we
want to make an exact copy of the data in our "Persons" table.
We use the following SQL statement:
SELECT *
INTO Persons_Backup
FROM Persons
INTO Persons_Backup
FROM Persons
We can also use the IN clause to copy the table into another
database:
SELECT *
INTO Persons_Backup IN 'Backup.mdb'
FROM Persons
INTO Persons_Backup IN 'Backup.mdb'
FROM Persons
We can also copy only a few fields into the new table:
SELECT
LastName,FirstName
INTO Persons_Backup
FROM Persons
INTO Persons_Backup
FROM Persons
SQL SELECT INTO - With a
WHERE Clause
We can also add a WHERE clause.
The following SQL statement creates a "Persons_Backup"
table with only the persons who lives in the city "Sandnes":
SELECT
LastName,Firstname
INTO Persons_Backup
FROM Persons
WHERE City='Sandnes'
INTO Persons_Backup
FROM Persons
WHERE City='Sandnes'
SQL SELECT INTO - Joined
Tables
Selecting data from more than one table is also possible.
The following example creates a "Persons_Order_Backup"
table contains data from the two tables "Persons" and
"Orders":
SELECT
Persons.LastName,Orders.OrderNo
INTO Persons_Order_Backup
FROM Persons
INNER JOIN Orders
ON Persons.P_Id=Orders.P_Id
INTO Persons_Order_Backup
FROM Persons
INNER JOIN Orders
ON Persons.P_Id=Orders.P_Id
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