MySQL :: MySQL 8.0 Reference Manual :: 15.2.7 INSERT Statement (original) (raw)
15.2.7 INSERT Statement
INSERT [LOW_PRIORITY | DELAYED | HIGH_PRIORITY] [IGNORE]
[INTO] tbl_name
[PARTITION (partition_name [, partition_name] ...)]
[(col_name [, col_name] ...)]
{ {VALUES | VALUE} (value_list) [, (value_list)] ... }
[AS row_alias[(col_alias [, col_alias] ...)]]
[ON DUPLICATE KEY UPDATE assignment_list]
INSERT [LOW_PRIORITY | DELAYED | HIGH_PRIORITY] [IGNORE]
[INTO] tbl_name
[PARTITION (partition_name [, partition_name] ...)]
SET assignment_list
[AS row_alias[(col_alias [, col_alias] ...)]]
[ON DUPLICATE KEY UPDATE assignment_list]
INSERT [LOW_PRIORITY | HIGH_PRIORITY] [IGNORE]
[INTO] tbl_name
[PARTITION (partition_name [, partition_name] ...)]
[(col_name [, col_name] ...)]
{ SELECT ...
| TABLE table_name
| VALUES row_constructor_list
}
[ON DUPLICATE KEY UPDATE assignment_list]
value:
{expr | DEFAULT}
value_list:
value [, value] ...
row_constructor_list:
ROW(value_list)[, ROW(value_list)][, ...]
assignment:
col_name =
value
| [row_alias.]col_name
| [tbl_name.]col_name
| [row_alias.]col_alias
assignment_list:
assignment [, assignment] ...
INSERT inserts new rows into an existing table. The INSERT ... VALUES,INSERT ... VALUES ROW(), andINSERT ... SET forms of the statement insert rows based on explicitly specified values. The INSERT ... SELECT form inserts rows selected from another table or tables. You can also useINSERT ... TABLE in MySQL 8.0.19 and later to insert rows from a single table.INSERT with an ON DUPLICATE KEY UPDATE
clause enables existing rows to be updated if a row to be inserted would cause a duplicate value in aUNIQUE
index or PRIMARY KEY
. In MySQL 8.0.19 and later, a row alias with one or more optional column aliases can be used with ON DUPLICATE KEY UPDATE
to refer to the row to be inserted.
For additional information aboutINSERT ... SELECT andINSERT ... ON DUPLICATE KEY UPDATE, seeSection 15.2.7.1, “INSERT ... SELECT Statement”, andSection 15.2.7.2, “INSERT ... ON DUPLICATE KEY UPDATE Statement”.
In MySQL 8.0, the DELAYED
keyword is accepted but ignored by the server. For the reasons for this, see Section 15.2.7.3, “INSERT DELAYED Statement”,
Inserting into a table requires theINSERT privilege for the table. If the ON DUPLICATE KEY UPDATE
clause is used and a duplicate key causes an UPDATE to be performed instead, the statement requires theUPDATE privilege for the columns to be updated. For columns that are read but not modified you need only the SELECT privilege (such as for a column referenced only on the right hand side of an_colname
=expr
_ assignment in an ON DUPLICATE KEY UPDATE
clause).
When inserting into a partitioned table, you can control which partitions and subpartitions accept new rows. ThePARTITION
clause takes a list of the comma-separated names of one or more partitions or subpartitions (or both) of the table. If any of the rows to be inserted by a given INSERT statement do not match one of the partitions listed, theINSERT statement fails with the error Found a row not matching the given partition set. For more information and examples, seeSection 26.5, “Partition Selection”.
tblname
is the table into which rows should be inserted. Specify the columns for which the statement provides values as follows:
- Provide a parenthesized list of comma-separated column names following the table name. In this case, a value for each named column must be provided by the
VALUES
list,VALUES ROW() list, or SELECT statement. For theINSERT TABLE
form, the number of columns in the source table must match the number of columns to be inserted. - If you do not specify a list of column names forINSERT ... VALUES orINSERT ... SELECT, values for every column in the table must be provided by the
VALUES
list,SELECT statement, orTABLE statement. If you do not know the order of the columns in the table, useDESCRIBE_`tblname`_
to find out. - A
SET
clause indicates columns explicitly by name, together with the value to assign each one.
Column values can be given in several ways:
- If strict SQL mode is not enabled, any column not explicitly given a value is set to its default (explicit or implicit) value. For example, if you specify a column list that does not name all the columns in the table, unnamed columns are set to their default values. Default value assignment is described inSection 13.6, “Data Type Default Values”. See alsoSection 1.6.3.3, “Enforced Constraints on Invalid Data”.
If strict SQL mode is enabled, anINSERT statement generates an error if it does not specify an explicit value for every column that has no default value. SeeSection 7.1.11, “Server SQL Modes”. - If both the column list and the
VALUES
list are empty, INSERT creates a row with each column set to its default value:
INSERT INTO tbl_name () VALUES();
If strict mode is not enabled, MySQL uses the implicit default value for any column that has no explicitly defined default. If strict mode is enabled, an error occurs if any column has no default value.
- Use the keyword
DEFAULT
to set a column explicitly to its default value. This makes it easier to writeINSERT statements that assign values to all but a few columns, because it enables you to avoid writing an incompleteVALUES
list that does not include a value for each column in the table. Otherwise, you must provide the list of column names corresponding to each value in theVALUES
list. - If a generated column is inserted into explicitly, the only permitted value is
DEFAULT
. For information about generated columns, seeSection 15.1.20.8, “CREATE TABLE and Generated Columns”. - In expressions, you can useDEFAULT(col_name) to produce the default value for column_
colname
_. - Type conversion of an expression_
expr
_ that provides a column value might occur if the expression data type does not match the column data type. Conversion of a given value can result in different inserted values depending on the column type. For example, inserting the string'1999.0e-2'
into an INT,FLOAT,DECIMAL(10,6), orYEAR column inserts the value1999
,19.9921
,19.992100
, or1999
, respectively. The value stored in theINT andYEAR columns is1999
because the string-to-number conversion looks only at as much of the initial part of the string as may be considered a valid integer or year. For theFLOAT andDECIMAL columns, the string-to-number conversion considers the entire string a valid numeric value. - An expression
expr
can refer to any column that was set earlier in a value list. For example, you can do this because the value forcol2
refers tocol1
, which has previously been assigned:
INSERT INTO tbl_name (col1,col2) VALUES(15,col1*2);
But the following is not legal, because the value forcol1
refers to col2
, which is assigned after col1
:
INSERT INTO tbl_name (col1,col2) VALUES(col2*2,15);
An exception occurs for columns that containAUTO_INCREMENT
values. BecauseAUTO_INCREMENT
values are generated after other value assignments, any reference to anAUTO_INCREMENT
column in the assignment returns a 0
.
INSERT statements that useVALUES
syntax can insert multiple rows. To do this, include multiple lists of comma-separated column values, with lists enclosed within parentheses and separated by commas. Example:
INSERT INTO tbl_name (a,b,c)
VALUES(1,2,3), (4,5,6), (7,8,9);
Each values list must contain exactly as many values as are to be inserted per row. The following statement is invalid because it contains one list of nine values, rather than three lists of three values each:
INSERT INTO tbl_name (a,b,c) VALUES(1,2,3,4,5,6,7,8,9);
VALUE
is a synonym forVALUES
in this context. Neither implies anything about the number of values lists, nor about the number of values per list. Either may be used whether there is a single values list or multiple lists, and regardless of the number of values per list.
INSERT statements usingVALUES ROW() syntax can also insert multiple rows. In this case, each value list must be contained within a ROW()
(row constructor), like this:
INSERT INTO tbl_name (a,b,c)
VALUES ROW(1,2,3), ROW(4,5,6), ROW(7,8,9);
The affected-rows value for anINSERT can be obtained using theROW_COUNT() SQL function or themysql_affected_rows() C API function. See Section 14.15, “Information Functions”, andmysql_affected_rows().
If you use INSERT ... VALUES or INSERT ... VALUES ROW()
with multiple value lists, orINSERT ... SELECT or INSERT ... TABLE
, the statement returns an information string in this format:
Records: N1 Duplicates: N2 Warnings: N3
If you are using the C API, the information string can be obtained by invoking the mysql_info() function. See mysql_info().
Records
indicates the number of rows processed by the statement. (This is not necessarily the number of rows actually inserted because Duplicates
can be nonzero.) Duplicates
indicates the number of rows that could not be inserted because they would duplicate some existing unique index value. Warnings
indicates the number of attempts to insert column values that were problematic in some way. Warnings can occur under any of the following conditions:
- Inserting
NULL
into a column that has been declaredNOT NULL
. For multiple-rowINSERT statements orINSERT INTO ... SELECT statements, the column is set to the implicit default value for the column data type. This is0
for numeric types, the empty string (''
) for string types, and the“zero” value for date and time types.INSERT INTO ... SELECT statements are handled the same way as multiple-row inserts because the server does not examine the result set from the SELECT to see whether it returns a single row. (For a single-rowINSERT, no warning occurs whenNULL
is inserted into aNOT NULL
column. Instead, the statement fails with an error.) - Setting a numeric column to a value that lies outside the column range. The value is clipped to the closest endpoint of the range.
- Assigning a value such as
'10.34 a'
to a numeric column. The trailing nonnumeric text is stripped off and the remaining numeric part is inserted. If the string value has no leading numeric part, the column is set to0
. - Inserting a string into a string column (CHAR,VARCHAR,TEXT, orBLOB) that exceeds the column maximum length. The value is truncated to the column maximum length.
- Inserting a value into a date or time column that is illegal for the data type. The column is set to the appropriate zero value for the type.
- For INSERT examples involving
AUTO_INCREMENT
column values, seeSection 5.6.9, “Using AUTO_INCREMENT”.
If INSERT inserts a row into a table that has anAUTO_INCREMENT
column, you can find the value used for that column by using theLAST_INSERT_ID() SQL function or the mysql_insert_id() C API function.
The INSERT statement supports the following modifiers:
- If you use the
LOW_PRIORITY
modifier, execution of the INSERT is delayed until no other clients are reading from the table. This includes other clients that began reading while existing clients are reading, and while theINSERT LOW_PRIORITY
statement is waiting. It is possible, therefore, for a client that issues anINSERT LOW_PRIORITY
statement to wait for a very long time.LOW_PRIORITY
affects only storage engines that use only table-level locking (such asMyISAM
,MEMORY
, andMERGE
). - If you specify
HIGH_PRIORITY
, it overrides the effect of the--low-priority-updates option if the server was started with that option. It also causes concurrent inserts not to be used. SeeSection 10.11.3, “Concurrent Inserts”.HIGH_PRIORITY
affects only storage engines that use only table-level locking (such asMyISAM
,MEMORY
, andMERGE
). - If you use the
IGNORE
modifier, ignorable errors that occur while executing theINSERT statement are ignored. For example, withoutIGNORE
, a row that duplicates an existingUNIQUE
index orPRIMARY KEY
value in the table causes a duplicate-key error and the statement is aborted. WithIGNORE
, the row is discarded and no error occurs. Ignored errors generate warnings instead.IGNORE
has a similar effect on inserts into partitioned tables where no partition matching a given value is found. WithoutIGNORE
, suchINSERT statements are aborted with an error. WhenINSERT IGNORE is used, the insert operation fails silently for rows containing the unmatched value, but inserts rows that are matched. For an example, seeSection 26.2.2, “LIST Partitioning”.
Data conversions that would trigger errors abort the statement ifIGNORE
is not specified. WithIGNORE
, invalid values are adjusted to the closest values and inserted; warnings are produced but the statement does not abort. You can determine with themysql_info() C API function how many rows were actually inserted into the table.
For more information, seeThe Effect of IGNORE on Statement Execution.
You can use REPLACE instead ofINSERT to overwrite old rows.REPLACE is the counterpart toINSERT IGNORE in the treatment of new rows that contain unique key values that duplicate old rows: The new rows replace the old rows rather than being discarded. SeeSection 15.2.12, “REPLACE Statement”. - If you specify
ON DUPLICATE KEY UPDATE
, and a row is inserted that would cause a duplicate value in aUNIQUE
index orPRIMARY KEY
, an UPDATE of the old row occurs. The affected-rows value per row is 1 if the row is inserted as a new row, 2 if an existing row is updated, and 0 if an existing row is set to its current values. If you specify theCLIENT_FOUND_ROWS
flag to themysql_real_connect() C API function when connecting to mysqld, the affected-rows value is 1 (not 0) if an existing row is set to its current values. See Section 15.2.7.2, “INSERT ... ON DUPLICATE KEY UPDATE Statement”. - INSERT DELAYED was deprecated in MySQL 5.6, and is scheduled for eventual removal. In MySQL 8.0, the
DELAYED
modifier is accepted but ignored. UseINSERT
(withoutDELAYED
) instead. SeeSection 15.2.7.3, “INSERT DELAYED Statement”.