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INSERT
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INSERT

INSERT — create new rows in a table

Synopsis

[ WITH [ RECURSIVE ]with_query [, ...] ]INSERT INTOtable_name [ ASalias ] [ (column_name [, ...] ) ]    [ OVERRIDING { SYSTEM | USER } VALUE ]    { DEFAULT VALUES | VALUES ( {expression | DEFAULT } [, ...] ) [, ...] |query }    [ ON CONFLICT [conflict_target ]conflict_action ]    [ RETURNING { * |output_expression [ [ AS ]output_name ] } [, ...] ]whereconflict_target can be one of:    ( {index_column_name | (index_expression ) } [ COLLATEcollation ] [opclass ] [, ...] ) [ WHEREindex_predicate ]    ON CONSTRAINTconstraint_nameandconflict_action is one of:    DO NOTHING    DO UPDATE SET {column_name = {expression | DEFAULT } |                    (column_name [, ...] ) = [ ROW ] ( {expression | DEFAULT } [, ...] ) |                    (column_name [, ...] ) = (sub-SELECT )                  } [, ...]              [ WHEREcondition ]

Description

INSERT inserts new rows into a table. One can insert one or more rows specified by value expressions, or zero or more rows resulting from a query.

The target column names can be listed in any order. If no list of column names is given at all, the default is all the columns of the table in their declared order; or the firstN column names, if there are onlyN columns supplied by theVALUES clause orquery. The values supplied by theVALUES clause orquery are associated with the explicit or implicit column list left-to-right.

Each column not present in the explicit or implicit column list will be filled with a default value, either its declared default value or null if there is none.

If the expression for any column is not of the correct data type, automatic type conversion will be attempted.

INSERT into tables that lack unique indexes will not be blocked by concurrent activity. Tables with unique indexes might block if concurrent sessions perform actions that lock or modify rows matching the unique index values being inserted; the details are covered inSection 59.5.ON CONFLICT can be used to specify an alternative action to raising a unique constraint or exclusion constraint violation error. (SeeON CONFLICT Clause below.)

The optionalRETURNING clause causesINSERT to compute and return value(s) based on each row actually inserted (or updated, if anON CONFLICT DO UPDATE clause was used). This is primarily useful for obtaining values that were supplied by defaults, such as a serial sequence number. However, any expression using the table's columns is allowed. The syntax of theRETURNING list is identical to that of the output list ofSELECT. Only rows that were successfully inserted or updated will be returned. For example, if a row was locked but not updated because anON CONFLICT DO UPDATE ... WHERE clausecondition was not satisfied, the row will not be returned.

You must haveINSERT privilege on a table in order to insert into it. IfON CONFLICT DO UPDATE is present,UPDATE privilege on the table is also required.

If a column list is specified, you only needINSERT privilege on the listed columns. Similarly, whenON CONFLICT DO UPDATE is specified, you only needUPDATE privilege on the column(s) that are listed to be updated. However,ON CONFLICT DO UPDATE also requiresSELECT privilege on any column whose values are read in theON CONFLICT DO UPDATE expressions orcondition.

Use of theRETURNING clause requiresSELECT privilege on all columns mentioned inRETURNING. If you use thequery clause to insert rows from a query, you of course need to haveSELECT privilege on any table or column used in the query.

Parameters

Inserting

This section covers parameters that may be used when only inserting new rows. Parametersexclusively used with theON CONFLICT clause are described separately.

with_query

TheWITH clause allows you to specify one or more subqueries that can be referenced by name in theINSERT query. SeeSection 7.8 andSELECT for details.

It is possible for thequery (SELECT statement) to also contain aWITH clause. In such a case both sets ofwith_query can be referenced within thequery, but the second one takes precedence since it is more closely nested.

table_name

The name (optionally schema-qualified) of an existing table.

alias

A substitute name fortable_name. When an alias is provided, it completely hides the actual name of the table. This is particularly useful whenON CONFLICT DO UPDATE targets a table namedexcluded, since that will otherwise be taken as the name of the special table representing the row proposed for insertion.

column_name

The name of a column in the table named bytable_name. The column name can be qualified with a subfield name or array subscript, if needed. (Inserting into only some fields of a composite column leaves the other fields null.) When referencing a column withON CONFLICT DO UPDATE, do not include the table's name in the specification of a target column. For example,INSERT INTO table_name ... ON CONFLICT DO UPDATE SET table_name.col = 1 is invalid (this follows the general behavior forUPDATE).

OVERRIDING SYSTEM VALUE

If this clause is specified, then any values supplied for identity columns will override the default sequence-generated values.

For an identity column defined asGENERATED ALWAYS, it is an error to insert an explicit value (other thanDEFAULT) without specifying eitherOVERRIDING SYSTEM VALUE orOVERRIDING USER VALUE. (For an identity column defined asGENERATED BY DEFAULT,OVERRIDING SYSTEM VALUE is the normal behavior and specifying it does nothing, butPostgreSQL allows it as an extension.)

OVERRIDING USER VALUE

If this clause is specified, then any values supplied for identity columns are ignored and the default sequence-generated values are applied.

This clause is useful for example when copying values between tables. WritingINSERT INTO tbl2 OVERRIDING USER VALUE SELECT * FROM tbl1 will copy fromtbl1 all columns that are not identity columns intbl2 while values for the identity columns intbl2 will be generated by the sequences associated withtbl2.

DEFAULT VALUES

All columns will be filled with their default values, as ifDEFAULT were explicitly specified for each column. (AnOVERRIDING clause is not permitted in this form.)

expression

An expression or value to assign to the corresponding column.

DEFAULT

The corresponding column will be filled with its default value. An identity column will be filled with a new value generated by the associated sequence. For a generated column, specifying this is permitted but merely specifies the normal behavior of computing the column from its generation expression.

query

A query (SELECT statement) that supplies the rows to be inserted. Refer to theSELECT statement for a description of the syntax.

output_expression

An expression to be computed and returned by theINSERT command after each row is inserted or updated. The expression can use any column names of the table named bytable_name. Write* to return all columns of the inserted or updated row(s).

output_name

A name to use for a returned column.

`ON CONFLICT` Clause

The optionalON CONFLICT clause specifies an alternative action to raising a unique violation or exclusion constraint violation error. For each individual row proposed for insertion, either the insertion proceeds, or, if anarbiter constraint or index specified byconflict_target is violated, the alternativeconflict_action is taken.ON CONFLICT DO NOTHING simply avoids inserting a row as its alternative action.ON CONFLICT DO UPDATE updates the existing row that conflicts with the row proposed for insertion as its alternative action.

conflict_target can performunique index inference. When performing inference, it consists of one or moreindex_column_name columns and/orindex_expression expressions, and an optionalindex_predicate. Alltable_name unique indexes that, without regard to order, contain exactly theconflict_target-specified columns/expressions are inferred (chosen) as arbiter indexes. If anindex_predicate is specified, it must, as a further requirement for inference, satisfy arbiter indexes. Note that this means a non-partial unique index (a unique index without a predicate) will be inferred (and thus used byON CONFLICT) if such an index satisfying every other criteria is available. If an attempt at inference is unsuccessful, an error is raised.

ON CONFLICT DO UPDATE guarantees an atomicINSERT orUPDATE outcome; provided there is no independent error, one of those two outcomes is guaranteed, even under high concurrency. This is also known asUPSERT —“UPDATE or INSERT”.

conflict_target

Specifies which conflictsON CONFLICT takes the alternative action on by choosingarbiter indexes. Either performsunique index inference, or names a constraint explicitly. ForON CONFLICT DO NOTHING, it is optional to specify aconflict_target; when omitted, conflicts with all usable constraints (and unique indexes) are handled. ForON CONFLICT DO UPDATE, aconflict_targetmust be provided.

conflict_action

conflict_action specifies an alternativeON CONFLICT action. It can be eitherDO NOTHING, or aDO UPDATE clause specifying the exact details of theUPDATE action to be performed in case of a conflict. TheSET andWHERE clauses inON CONFLICT DO UPDATE have access to the existing row using the table's name (or an alias), and to the row proposed for insertion using the specialexcluded table.SELECT privilege is required on any column in the target table where correspondingexcluded columns are read.

Note that the effects of all per-rowBEFORE INSERT triggers are reflected inexcluded values, since those effects may have contributed to the row being excluded from insertion.

index_column_name

The name of atable_name column. Used to infer arbiter indexes. FollowsCREATE INDEX format.SELECT privilege onindex_column_name is required.

index_expression

Similar toindex_column_name, but used to infer expressions ontable_name columns appearing within index definitions (not simple columns). FollowsCREATE INDEX format.SELECT privilege on any column appearing withinindex_expression is required.

collation

When specified, mandates that correspondingindex_column_name orindex_expression use a particular collation in order to be matched during inference. Typically this is omitted, as collations usually do not affect whether or not a constraint violation occurs. FollowsCREATE INDEX format.

opclass

When specified, mandates that correspondingindex_column_name orindex_expression use particular operator class in order to be matched during inference. Typically this is omitted, as theequality semantics are often equivalent across a type's operator classes anyway, or because it's sufficient to trust that the defined unique indexes have the pertinent definition of equality. FollowsCREATE INDEX format.

index_predicate

Used to allow inference of partial unique indexes. Any indexes that satisfy the predicate (which need not actually be partial indexes) can be inferred. FollowsCREATE INDEX format.SELECT privilege on any column appearing withinindex_predicate is required.

constraint_name

Explicitly specifies an arbiterconstraint by name, rather than inferring a constraint or index.

condition

An expression that returns a value of typeboolean. Only rows for which this expression returnstrue will be updated, although all rows will be locked when theON CONFLICT DO UPDATE action is taken. Note thatcondition is evaluated last, after a conflict has been identified as a candidate to update.

Note that exclusion constraints are not supported as arbiters withON CONFLICT DO UPDATE. In all cases, onlyNOT DEFERRABLE constraints and unique indexes are supported as arbiters.

INSERT with anON CONFLICT DO UPDATE clause is a“deterministic” statement. This means that the command will not be allowed to affect any single existing row more than once; a cardinality violation error will be raised when this situation arises. Rows proposed for insertion should not duplicate each other in terms of attributes constrained by an arbiter index or constraint.

Note that it is currently not supported for theON CONFLICT DO UPDATE clause of anINSERT applied to a partitioned table to update the partition key of a conflicting row such that it requires the row be moved to a new partition.

Tip

It is often preferable to use unique index inference rather than naming a constraint directly usingON CONFLICT ON CONSTRAINT constraint_name. Inference will continue to work correctly when the underlying index is replaced by another more or less equivalent index in an overlapping way, for example when usingCREATE UNIQUE INDEX ... CONCURRENTLY before dropping the index being replaced.

Outputs

On successful completion, anINSERT command returns a command tag of the form

INSERToidcount

Thecount is the number of rows inserted or updated.oid is always 0 (it used to be theOID assigned to the inserted row ifcount was exactly one and the target table was declaredWITH OIDS and 0 otherwise, but creating a tableWITH OIDS is not supported anymore).

If theINSERT command contains aRETURNING clause, the result will be similar to that of aSELECT statement containing the columns and values defined in theRETURNING list, computed over the row(s) inserted or updated by the command.

Notes

If the specified table is a partitioned table, each row is routed to the appropriate partition and inserted into it. If the specified table is a partition, an error will occur if one of the input rows violates the partition constraint.

Examples

Insert a single row into tablefilms:

INSERT INTO films VALUES    ('UA502', 'Bananas', 105, '1971-07-13', 'Comedy', '82 minutes');

In this example, thelen column is omitted and therefore it will have the default value:

INSERT INTO films (code, title, did, date_prod, kind)    VALUES ('T_601', 'Yojimbo', 106, '1961-06-16', 'Drama');

This example uses theDEFAULT clause for the date columns rather than specifying a value:

INSERT INTO films VALUES    ('UA502', 'Bananas', 105, DEFAULT, 'Comedy', '82 minutes');INSERT INTO films (code, title, did, date_prod, kind)    VALUES ('T_601', 'Yojimbo', 106, DEFAULT, 'Drama');

To insert a row consisting entirely of default values:

INSERT INTO films DEFAULT VALUES;

To insert multiple rows using the multirowVALUES syntax:

INSERT INTO films (code, title, did, date_prod, kind) VALUES    ('B6717', 'Tampopo', 110, '1985-02-10', 'Comedy'),    ('HG120', 'The Dinner Game', 140, DEFAULT, 'Comedy');

This example inserts some rows into tablefilms from a tabletmp_films with the same column layout asfilms:

INSERT INTO films SELECT * FROM tmp_films WHERE date_prod < '2004-05-07';

This example inserts into array columns:

-- Create an empty 3x3 gameboard for noughts-and-crossesINSERT INTO tictactoe (game, board[1:3][1:3])    VALUES (1, '{{" "," "," "},{" "," "," "},{" "," "," "}}');-- The subscripts in the above example aren't really neededINSERT INTO tictactoe (game, board)    VALUES (2, '{{X," "," "},{" ",O," "},{" ",X," "}}');

Insert a single row into tabledistributors, returning the sequence number generated by theDEFAULT clause:

INSERT INTO distributors (did, dname) VALUES (DEFAULT, 'XYZ Widgets')   RETURNING did;

Increment the sales count of the salesperson who manages the account for Acme Corporation, and record the whole updated row along with current time in a log table:

WITH upd AS (  UPDATE employees SET sales_count = sales_count + 1 WHERE id =    (SELECT sales_person FROM accounts WHERE name = 'Acme Corporation')    RETURNING *)INSERT INTO employees_log SELECT *, current_timestamp FROM upd;

Insert or update new distributors as appropriate. Assumes a unique index has been defined that constrains values appearing in thedid column. Note that the specialexcluded table is used to reference values originally proposed for insertion:

INSERT INTO distributors (did, dname)    VALUES (5, 'Gizmo Transglobal'), (6, 'Associated Computing, Inc')    ON CONFLICT (did) DO UPDATE SET dname = EXCLUDED.dname;

Insert a distributor, or do nothing for rows proposed for insertion when an existing, excluded row (a row with a matching constrained column or columns after before row insert triggers fire) exists. Example assumes a unique index has been defined that constrains values appearing in thedid column:

INSERT INTO distributors (did, dname) VALUES (7, 'Redline GmbH')    ON CONFLICT (did) DO NOTHING;

Insert or update new distributors as appropriate. Example assumes a unique index has been defined that constrains values appearing in thedid column.WHERE clause is used to limit the rows actually updated (any existing row not updated will still be locked, though):

-- Don't update existing distributors based in a certain ZIP codeINSERT INTO distributors AS d (did, dname) VALUES (8, 'Anvil Distribution')    ON CONFLICT (did) DO UPDATE    SET dname = EXCLUDED.dname || ' (formerly ' || d.dname || ')'    WHERE d.zipcode <> '21201';-- Name a constraint directly in the statement (uses associated-- index to arbitrate taking the DO NOTHING action)INSERT INTO distributors (did, dname) VALUES (9, 'Antwerp Design')    ON CONFLICT ON CONSTRAINT distributors_pkey DO NOTHING;

Insert new distributor if possible; otherwiseDO NOTHING. Example assumes a unique index has been defined that constrains values appearing in thedid column on a subset of rows where theis_active Boolean column evaluates totrue:

-- This statement could infer a partial unique index on "did"-- with a predicate of "WHERE is_active", but it could also-- just use a regular unique constraint on "did"INSERT INTO distributors (did, dname) VALUES (10, 'Conrad International')    ON CONFLICT (did) WHERE is_active DO NOTHING;

Compatibility

INSERT conforms to the SQL standard, except that theRETURNING clause is aPostgres Pro extension, as is the ability to useWITH withINSERT, and the ability to specify an alternative action withON CONFLICT. Also, the case in which a column name list is omitted, but not all the columns are filled from theVALUES clause orquery, is disallowed by the standard.

The SQL standard specifies thatOVERRIDING SYSTEM VALUE can only be specified if an identity column that is generated always exists. Postgres Pro allows the clause in any case and ignores it if it is not applicable.

Possible limitations of thequery clause are documented under SELECT.

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