INSERT

INSERT — create new rows in a table

Synopsis

[ WITH [ RECURSIVE ] 
with_query
 [, ...] ]
INSERT INTO 
table_name
 [ AS 
alias
 ] [ ( 
column_name
 [, ...] ) ]
    [ OVERRIDING { SYSTEM | USER} VALUE ]
    { DEFAULT VALUES | VALUES ( { 
expression
 | DEFAULT } [, ...] ) [, ...] | 
query
 }
    [ ON CONFLICT [ 
conflict_target
 ] 
conflict_action
 ]
    [ RETURNING * | 
output_expression
 [ [ AS ] 
output_name
 ] [, ...] ]


where 
conflict_target
 can be one of:


    ( { 
index_column_name
 | ( 
index_expression
 ) } [ COLLATE 
collation
 ] [ 
opclass
 ] [, ...] ) [ WHERE 
index_predicate
 ]
    ON CONSTRAINT 
constraint_name
and 
conflict_action
 is one of:


    DO NOTHING
    DO UPDATE SET { 
column_name
 = { 
expression
 | DEFAULT } |
                    ( 
column_name
 [, ...] ) = [ ROW ] ( { 
expression
 | DEFAULT } [, ...] ) |
                    ( 
column_name
 [, ...] ) = ( 
sub-SELECT
 )
                  } [, ...]
              [ WHERE 
condition
 ]

Description

INSERTinserts 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 onlyNcolumns supplied by theVALUESclause orquery. The values supplied by theVALUESclause 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.

ON CONFLICTcan be used to specify an alternative action to raising a unique constraint or exclusion constraint violation error. (SeeON CONFLICTClausebelow.)

The optionalRETURNINGclause causesINSERTto compute and return value(s) based on each row actually inserted (or updated, if anON CONFLICT DO UPDATEclause 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 theRETURNINGlist 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 ... WHEREclause_condition_was not satisfied, the row will not be returned.

You must haveINSERTprivilege on a table in order to insert into it. IfON CONFLICT DO UPDATEis present,UPDATEprivilege on the table is also required.

If a column list is specified, you only needINSERTprivilege on the listed columns. Similarly, whenON CONFLICT DO UPDATEis specified, you only needUPDATEprivilege on the column(s) that are listed to be updated. However,ON CONFLICT DO UPDATEalso requiresSELECTprivilege on any column whose values are read in theON CONFLICT DO UPDATEexpressions orcondition.

Use of theRETURNINGclause requiresSELECTprivilege on all columns mentioned inRETURNING. If you use the_query_clause to insert rows from a query, you of course need to haveSELECTprivilege on any table or column used in the query.

Parameters

Inserting

This section covers parameters that may be used when only inserting new rows. Parameters_exclusively_used with theON CONFLICTclause are described separately.

with_query

TheWITHclause allows you to specify one or more subqueries that can be referenced by name in theINSERTquery. SeeSection 7.8andSELECTfor details.

It is possible for thequery(SELECTstatement) to also contain aWITHclause. 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 UPDATEtargets a table namedexcluded, since that will otherwise be taken as the name of the special table representing rows 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 = 1is invalid (this follows the general behavior forUPDATE).

OVERRIDING SYSTEM VALUE

Without this clause, it is an error to specify an explicit value (other thanDEFAULT) for an identity column defined asGENERATED ALWAYS. This clause overrides that restriction.

OVERRIDING USER VALUE

If this clause is specified, then any values supplied for identity columns defined asGENERATED BY DEFAULTare 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 tbl1will copy fromtbl1all columns that are not identity columns intbl2while values for the identity columns intbl2will be generated by the sequences associated withtbl2.

DEFAULT VALUES

All columns will be filled with their default values. (AnOVERRIDINGclause 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.

query

A query (SELECTstatement) that supplies the rows to be inserted. Refer to theSELECTstatement for a description of the syntax.

output_expression

An expression to be computed and returned by theINSERTcommand 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 CONFLICTClause

The optionalON CONFLICTclause 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_targetis violated, the alternativeconflict_action_is taken.ON CONFLICT DO NOTHINGsimply avoids inserting a row as its alternative action.ON CONFLICT DO UPDATEupdates the existing row that conflicts with the row proposed for insertion as its alternative action.

conflict_target_can perform_unique index inference. When performing inference, it consists of one or moreindex_column_name_columns and/orindex_expressionexpressions, and an optionalindex_predicate. Alltable_nameunique 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 UPDATEguarantees an atomicINSERTorUPDATEoutcome; 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 CONFLICTtakes 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, a_conflict_targetmust_be provided.

conflict_action

_conflict_action_specifies an alternativeON CONFLICTaction. It can be eitherDO NOTHING, or aDO UPDATEclause specifying the exact details of theUPDATEaction to be performed in case of a conflict. TheSETandWHEREclauses inON CONFLICT DO UPDATEhave access to the existing row using the table's name (or an alias), and to rows proposed for insertion using the specialexcludedtable.SELECTprivilege is required on any column in the target table where correspondingexcludedcolumns are read.

Note that the effects of all per-rowBEFORE INSERTtriggers are reflected inexcludedvalues, 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 INDEXformat.SELECTprivilege 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 INDEXformat.SELECTprivilege 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 INDEXformat.

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 the_equality_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 INDEXformat.

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 INDEXformat.SELECTprivilege on any column appearing within_index_predicate_is required.

constraint_name

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

condition

An expression that returns a value of typeboolean. Only rows for which this expression returnstruewill be updated, although all rows will be locked when theON CONFLICT DO UPDATEaction is taken. Note that_condition_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 DEFERRABLEconstraints and unique indexes are supported as arbiters.

INSERTwith anON CONFLICT DO UPDATEclause 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.

Tip

It is often preferable to use unique index inference rather than naming a constraint directly usingON CONFLICT ON CONSTRAINTconstraint_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 ... CONCURRENTLYbefore dropping the index being replaced.

Outputs

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

INSERT 
oid
count

Thecount_is the number of rows inserted or updated. Ifcountis exactly one, and the target table has OIDs, thenoidis theOIDassigned to the inserted row. The single row must have been inserted rather than updated. Otherwiseoid_is zero.

If theINSERTcommand contains aRETURNINGclause, the result will be similar to that of aSELECTstatement containing the columns and values defined in theRETURNINGlist, 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, thelencolumn 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 theDEFAULTclause 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 multirowVALUESsyntax:

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 tablefilmsfrom a tabletmp_filmswith 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-crosses
INSERT INTO tictactoe (game, board[1:3][1:3])
    VALUES (1, '{{" "," "," "},{" "," "," "},{" "," "," "}}');
-- The subscripts in the above example aren't really needed
INSERT INTO tictactoe (game, board)
    VALUES (2, '{{X," "," "},{" ",O," "},{" ",X," "}}');

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

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 thedidcolumn. Note that the specialexcludedtable 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 thedidcolumn:

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 thedidcolumn.WHEREclause 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 code
INSERT 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 thedidcolumn on a subset of rows where theis_activeBoolean 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

INSERTconforms to the SQL standard, except that theRETURNINGclause is aPostgreSQLextension, as is the ability to useWITHwithINSERT, 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 theVALUESclause orquery, is disallowed by the standard.

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

Possible limitations of the_query_clause are documented underSELECT.