INSERT
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Inserts data into a table.
Syntax
INSERT [IGNORE] [INTO] <table_name> [(<column_name>,...)]
[VALUES | VALUE] (expr,...),(...),...
[ ON DUPLICATE KEY UPDATE
<column_name> = insert_expr
[, <column_name> = insert_expr] ... ]
INSERT [IGNORE] [INTO] <table_name> [(col_name,...)]
SELECT [WITH(force_random_reshuffle=1)] ...
[ ON DUPLICATE KEY UPDATE
<column_name> = insert_expr
[, <column_name> = insert_expr] ... ]
INSERT [IGNORE] [INTO] <table_name>
SET <column_name>=expr, ...
[ ON DUPLICATE KEY UPDATE
<column_name> = insert_expr
[, <column_name>= insert_expr] ... ]
insert_expr:
expr
| VALUES(<column_name>)
Remarks
-
A field of type
TIMESTAMP
orTIMESTAMP(6)
declared with theDEFAULT <value>
modifier will be set to<value>
if no explicit value is specified.Refer to the discussion of these types in the Data Types topic for more details. -
SingleStore supports constants,
DEFAULT
, or nullary builtins such asNOW()
,RAND()
, orUNIX_
for expressions (TIMESTAMP() expr
) for INSERTs. -
INSERT
queries will fail if themaximum_
limit has been reached.table_ memory Refer to Addressing the
Maximum Table Memory
Error for more information. -
INSERT IGNORE
discards rows with duplicate keys for both singleton and multi-row inserts.In this case, SingleStore discards records with duplicate keys and, without rolling back, continues inserting records with unique keys. This can speed up performance of multi-INSERT because it avoids an extra roundtrip between the aggregators and leaves. -
Multi-inserts are atomic in nature.
For a multi-insert transaction, either all the rows are committed or the transaction is rolled back. -
Multi-inserts may or may not have consecutive
AUTO_
values.INCREMENT See AUTO_ INCREMENT behavior for more information. -
When you use the
IGNORE
modifier, data conversion errors for a row being inserted are ignored, and the row will be inserted with default values for fields where the conversion failed. -
If the
ON DUPLICATE KEY UPDATE
clause is specified, and a row is to be inserted that would result in a duplicate value in aPRIMARY KEY
orUNIQUE
index, SingleStore will instead perform anUPDATE
of the old row. -
The
IGNORE
modifier andON DUPLICATE KEY UPDATE
clause cannot be used in the sameINSERT
query, because their semantics contradict each other.For more information, see Query Errors. -
When using
ON DUPLICATE KEY UPDATE
, the affected row count will be 0 if no existing row is changed, 1 if a new row is inserted, and 2 if an existing row is updated. -
ON DUPLICATE KEY UPDATE
cannot update unique key columns in columnstore tables.For rowstore tables, ON DUPLICATE KEY UPDATE
is allowed as long as the updated column isn't part of the table's explicitly defined shard key or primary key if there's no explicitly defined shard key. -
This command must be run on the master aggregator or a child aggregator node (see Cluster Management Commands).
-
INSERT .
into. . SELECT AUTO_
columns can only be pushed down to leaves if the source column is alsoINCREMENT AUTO_
, becauseINCREMENT AUTO_
values are generated on the aggregator.INCREMENT This prevents insertion of 0
orNULL
values in theAUTO_
column, if the source column isn’tINCREMENT AUTO_
.INCREMENT For more information, see AUTO_ INCREMENT Behavior. -
SingleStore supports
INSERT .
across databases.. . SELECT The column data types that are being inserted must match the column data types from selected table: INSERT INTO db2.test2.t2 (col1, col2, ...) SELECT col1, col2,... FROM db1.test1.t1; -
Writing to multiple databases in a transaction is not supported.
-
Scalar expression are not supported as part of the VALUES clause:
INSERT INTO t1 (col1, col2) VALUES ((SELECT col1 FROM t2 LIMIT 1), 1);
-
Refer to the Permission Matrix for the required permission.
force_ random_ reshuffle
To reduce skew, you can force the INSERT … SELECT
to redistribute the data with the force_
query hint.
On Duplicate Key Update
ON DUPLICATE KEY UPDATE
allows you to perform an upsert of a row.
Examples
Simple Insert
INSERT INTO mytbl (v) VALUES ("hello"), ("goodbye");
This example shows a successful insert even when converting a NULL
value to an int NOT NULL
type, with the NULL
replaced by 0
:
CREATE TABLE mytbl2(a int not null);INSERT IGNORE mytbl2 VALUES(null);SELECT * FROM mytbl2;
+---+
| a |
+---+
| 0 |
+---+
1 row in set (0.24 sec)
ON DUPLICATE KEY UPDATE and force_ random_ reshuffle
This example shows a simple INSERT
with both ON DUPLICATE KEY UPDATE
and force_
.mytbl_
will be inserted into mytbl
, and distributed across partitions.
INSERT INTO mytbl (column1, column2, column3)SELECT WITH(force_random_reshuffle=1)* FROM mytbl_new ON DUPLICATE KEY UPDATEcolumn1 = VALUES(column1),column2 = VALUES(column2),column3 = VALUES(column3);
Query OK, 29 rows affected (0.18 sec)
Related Topics
Last modified: March 8, 2024