MySQL Copy Table With Examples?
Summary: in this tutorial, you will learn how to copy table within the same database or from one database to another using CREATE TABLE and SELECT statements.
MySQL copy table to a new table
Copying data from an existing table to a new one is very useful in some cases such as backing up data and replicating the production data for testing.
To copy data from a table to a new table, you use CREATE TABLE and SELECT statements as follows:
First, MySQL creates a new table with the name indicated in the CREATE TABLE statement. The structure of the new table is defined by the result set of the
SELECT
statement. Then, MySQL populates data that comes from the SELECT
statement to the new table.
To copy partial data from an existing table to the new one, you use WHERE clause in the SELECT statement as follows:
It is very important to check whether the table you want to create that already exists before creating it. To do so, you use
IF NOT EXIST
clause in the CREATE TABLE
statement. The complete command of copying data from an existing table to the new one is as follows:
Note that the statement above just copies the table and its data. It does not copy other database objects such as indexes, primary key constraint, foreign key constraints, triggers, etc., associated with the table.
To copy data from one table and also all the dependent objects of the table, you use the following statements:
We need to execute two statements. The first statement creates a new table
new_table
by duplicating the existing_table
. The second statement inserts data from the existing table into the new_table
.MySQL copy table examples
The following statement copies data from the
offices
table to a new table named offices_bk
in the classicmodels
sample database.
We can verify the copy by querying data from the
office_bk
table as follows:
In cases we want to copy the offices in the US only, we can add the
WHERE
clause to the SELECT
statement as follows:
The following statement gets all data from the
offices_usa
table.
Suppose, we want to copy not only the data but also all database objects associated with the
offices
table, we use the following statements:MySQL copy table to another database
Sometimes, you want to copy a table to a different database. In such cases you use the following statements:
The first statement creates a new table new_table in the destination database (destination_db) by duplicating the existing table (existing_table) from the source database (source_db).
The second statements copy data from the existing table in the source database to the new table in the destination database.
Let’s see the following example.
First, we create a database named testdb using the following statement:
Second, we create the
offices
table in the testdb
by copying its structure from the offices
table in the classicmodels
database.
Third, we copy data from the classimodels.offices table to testdb.offices table.
Let’s verify the data from the
testdb.offices
table.
In this tutorial, we have shown you various techniques to copy table within a database and from one database to another.
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