INSERT [LOW_PRIORITY | HIGH_PRIORITY] [IGNORE]
[INTO] tbl_name [(col_name,...)]
SELECT ...
[ ON DUPLICATE KEY UPDATE col_name=expr, ... ]
With INSERT ...
SELECT, you can quickly insert many rows into a table
from one or many tables. For example:
INSERT INTO tbl_temp2 (fld_id) SELECT tbl_temp1.fld_order_id FROM tbl_temp1 WHERE tbl_temp1.fld_order_id > 100;
The following conditions hold for a
INSERT ...
SELECT statements:
Specify
IGNOREto ignore rows that would cause duplicate-key violations.DELAYEDis ignored withINSERT ... SELECT.The target table of the
INSERTstatement may appear in theFROMclause of theSELECTpart of the query. (This was not possible in some older versions of MySQL.) However, you cannot insert into a table and select from the same table in a subquery.When selecting from and inserting into a table at the same time, MySQL creates a temporary table to hold the rows from the
SELECTand then inserts those rows into the target table. However, it remains true that you cannot useINSERT INTO t ... SELECT ... FROM twhentis aTEMPORARYtable, becauseTEMPORARYtables cannot be referred to twice in the same statement (see Section C.5.7.2, “TEMPORARYTable Problems”).AUTO_INCREMENTcolumns work as usual.To ensure that the binary log can be used to re-create the original tables, MySQL does not permit concurrent inserts for
INSERT ... SELECTstatements.To avoid ambiguous column reference problems when the
SELECTand theINSERTrefer to the same table, provide a unique alias for each table used in theSELECTpart, and qualify column names in that part with the appropriate alias.
In the values part of ON DUPLICATE KEY
UPDATE, you can refer to columns in other tables, as
long as you do not use GROUP BY in the
SELECT part. One side effect is
that you must qualify nonunique column names in the values part.
The order in which rows are returned by a
SELECT statement with no
ORDER BY clause is not determined. This means
that, when using replication, there is no guarantee that such a
SELECT returns rows in the same order on the
master and the slave; this can lead to inconsistencies between
them. To prevent this from occurring, you should always write
INSERT ... SELECT statements that are to be
replicated as INSERT ... SELECT ... ORDER BY
. The choice of
columncolumn does not matter as long as the
same order for returning the rows is enforced on both the master
and the slave. See also
Section 17.4.1.12, “Replication and LIMIT”.