Pre-General Availability Draft: 2018-02-25
CREATE TABLE new_tbl [AS] SELECT * FROM orig_tbl;
MySQL creates new columns for all elements in the
SELECT. For example:
mysql> CREATE TABLE test (a INT NOT NULL AUTO_INCREMENT, -> PRIMARY KEY (a), KEY(b)) -> ENGINE=MyISAM SELECT b,c FROM test2;
This creates a
MyISAM table with
ENGINE option is
part of the
statement, and should not be used following the
SELECT; this would result in a
syntax error. The same is true for other
CREATE TABLE options such as
Notice that the columns from the
SELECT statement are appended to
the right side of the table, not overlapped onto it. Take the
mysql> SELECT * FROM foo; +---+ | n | +---+ | 1 | +---+ mysql> CREATE TABLE bar (m INT) SELECT n FROM foo; Query OK, 1 row affected (0.02 sec) Records: 1 Duplicates: 0 Warnings: 0 mysql> SELECT * FROM bar; +------+---+ | m | n | +------+---+ | NULL | 1 | +------+---+ 1 row in set (0.00 sec)
For each row in table
foo, a row is inserted
bar with the values from
foo and default values for the new columns.
In a table resulting from
CREATE TABLE ...
SELECT, columns named only in the
CREATE TABLE part come first.
Columns named in both parts or only in the
SELECT part come after that. The
data type of
SELECT columns can
be overridden by also specifying the column in the
CREATE TABLE part.
If any errors occur while copying the data to the table, it is automatically dropped and not created.
You can precede the
indicate how to handle rows that duplicate unique key values.
IGNORE, rows that duplicate an existing
row on a unique key value are discarded. With
REPLACE, new rows replace rows that have the
same unique key value. If neither
REPLACE is specified, duplicate unique key
values result in an error. For more information, see
Comparison of the IGNORE Keyword and Strict SQL Mode.
Because the ordering of the rows in the underlying
SELECT statements cannot always
CREATE TABLE ... IGNORE SELECT
CREATE TABLE ... REPLACE SELECT
statements are flagged as unsafe for statement-based
replication. Such statements produce a warning in the error log
when using statement-based mode and are written to the binary
log using the row-based format when using
MIXED mode. See also
Section 188.8.131.52, “Advantages and Disadvantages of Statement-Based and Row-Based
CREATE TABLE ...
SELECT does not automatically create any indexes for
you. This is done intentionally to make the statement as
flexible as possible. If you want to have indexes in the created
table, you should specify these before the
mysql> CREATE TABLE bar (UNIQUE (n)) SELECT n FROM foo;
CREATE TABLE ... SELECT, the destination
table does not preserve information about whether columns in the
selected-from table are generated columns. The
SELECT part of the statement
cannot assign values to generated columns in the destination
Some conversion of data types might occur. For example, the
AUTO_INCREMENT attribute is not preserved,
VARCHAR columns can become
CHAR columns. Retrained
NULL) and, for those columns that have them,
COMMENT, and the
When creating a table with
TABLE ... SELECT, make sure to alias any function
calls or expressions in the query. If you do not, the
CREATE statement might fail or result in
undesirable column names.
CREATE TABLE artists_and_works SELECT artist.name, COUNT(work.artist_id) AS number_of_works FROM artist LEFT JOIN work ON artist.id = work.artist_id GROUP BY artist.id;
You can also explicitly specify the data type for a column in the created table:
CREATE TABLE foo (a TINYINT NOT NULL) SELECT b+1 AS a FROM bar;
... SELECT, if
IF NOT EXISTS is
given and the target table exists, nothing is inserted into the
destination table, and the statement is not logged.
To ensure that the binary log can be used to re-create the
original tables, MySQL does not permit concurrent inserts during
CREATE TABLE ...
You cannot use
FOR UPDATE as part of the
SELECT in a statement such as
TABLE . If you
attempt to do so, the statement fails.
new_table SELECT ... FROM