INSERT, UPDATE and DELETE statements build on a hierarchy starting with UpdateBase. The Insert and Update constructs build on the intermediary ValuesBase.
Construct Delete object.
Similar functionality is available via the delete() method on Table.
| Parameters: |
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See also
Deletes - SQL Expression Tutorial
Construct an Insert object.
Similar functionality is available via the insert() method on Table.
| Parameters: |
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If both values and compile-time bind parameters are present, the compile-time bind parameters override the information specified within values on a per-key basis.
The keys within values can be either Column objects or their string identifiers. Each key may reference one of:
If a SELECT statement is specified which references this INSERT statement’s table, the statement will be correlated against the INSERT statement.
See also
Insert Expressions - SQL Expression Tutorial
Inserts, Updates and Deletes - SQL Expression Tutorial
Construct an Update object.
E.g.:
from sqlalchemy import update
stmt = update(users).where(users.c.id==5).\
values(name='user #5')Similar functionality is available via the update() method on Table:
stmt = users.update().\
where(users.c.id==5).\
values(name='user #5')| Parameters: |
|
|---|
If both values and compile-time bind parameters are present, the compile-time bind parameters override the information specified within values on a per-key basis.
The keys within values can be either Column objects or their string identifiers (specifically the “key” of the Column, normally but not necessarily equivalent to its “name”). Normally, the Column objects used here are expected to be part of the target Table that is the table to be updated. However when using MySQL, a multiple-table UPDATE statement can refer to columns from any of the tables referred to in the WHERE clause.
The values referred to in values are typically:
When combining select() constructs within the values clause of an update() construct, the subquery represented by the select() should be correlated to the parent table, that is, providing criterion which links the table inside the subquery to the outer table being updated:
users.update().values(
name=select([addresses.c.email_address]).\
where(addresses.c.user_id==users.c.id).\
as_scalar()
)See also
Inserts, Updates and Deletes - SQL Expression Language Tutorial
Bases: sqlalchemy.sql.expression.UpdateBase
Represent a DELETE construct.
The Delete object is created using the delete() function.
Construct a new Delete object.
This constructor is mirrored as a public API function; see delete() for a full usage and argument description.
Add a new kind of dialect-specific keyword argument for this class.
E.g.:
Index.argument_for("mydialect", "length", None)
some_index = Index('a', 'b', mydialect_length=5)The DialectKWArgs.argument_for() method is a per-argument way adding extra arguments to the DefaultDialect.construct_arguments dictionary. This dictionary provides a list of argument names accepted by various schema-level constructs on behalf of a dialect.
New dialects should typically specify this dictionary all at once as a data member of the dialect class. The use case for ad-hoc addition of argument names is typically for end-user code that is also using a custom compilation scheme which consumes the additional arguments.
| Parameters: |
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New in version 0.9.4.
Return a ‘bind’ linked to this UpdateBase or a Table associated with it.
Compare this ClauseElement to the given ClauseElement.
Subclasses should override the default behavior, which is a straight identity comparison.
**kw are arguments consumed by subclass compare() methods and may be used to modify the criteria for comparison. (see ColumnElement)
Compile this SQL expression.
The return value is a Compiled object. Calling str() or unicode() on the returned value will yield a string representation of the result. The Compiled object also can return a dictionary of bind parameter names and values using the params accessor.
| Parameters: |
|
|---|
A collection of keyword arguments specified as dialect-specific options to this construct.
The arguments are present here in their original <dialect>_<kwarg> format. Only arguments that were actually passed are included; unlike the DialectKWArgs.dialect_options collection, which contains all options known by this dialect including defaults.
The collection is also writable; keys are accepted of the form <dialect>_<kwarg> where the value will be assembled into the list of options.
New in version 0.9.2.
Changed in version 0.9.4: The DialectKWArgs.dialect_kwargs collection is now writable.
See also
DialectKWArgs.dialect_options - nested dictionary form
A collection of keyword arguments specified as dialect-specific options to this construct.
This is a two-level nested registry, keyed to <dialect_name> and <argument_name>. For example, the postgresql_where argument would be locatable as:
arg = my_object.dialect_options['postgresql']['where']New in version 0.9.2.
See also
DialectKWArgs.dialect_kwargs - flat dictionary form
Compile and execute this Executable.
Set non-SQL options for the statement which take effect during execution.
Execution options can be set on a per-statement or per Connection basis. Additionally, the Engine and ORM Query objects provide access to execution options which they in turn configure upon connections.
The execution_options() method is generative. A new instance of this statement is returned that contains the options:
statement = select([table.c.x, table.c.y])
statement = statement.execution_options(autocommit=True)Note that only a subset of possible execution options can be applied to a statement - these include “autocommit” and “stream_results”, but not “isolation_level” or “compiled_cache”. See Connection.execution_options() for a full list of possible options.
A synonym for DialectKWArgs.dialect_kwargs.
Set the parameters for the statement.
This method raises NotImplementedError on the base class, and is overridden by ValuesBase to provide the SET/VALUES clause of UPDATE and INSERT.
Add one or more expressions following the statement keyword, i.e. SELECT, INSERT, UPDATE, or DELETE. Generative.
This is used to support backend-specific prefix keywords such as those provided by MySQL.
E.g.:
stmt = table.insert().prefix_with("LOW_PRIORITY", dialect="mysql")Multiple prefixes can be specified by multiple calls to prefix_with().
| Parameters: |
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|---|
Add a RETURNING or equivalent clause to this statement.
e.g.:
stmt = table.update().\
where(table.c.data == 'value').\
values(status='X').\
returning(table.c.server_flag,
table.c.updated_timestamp)
for server_flag, updated_timestamp in connection.execute(stmt):
print(server_flag, updated_timestamp)The given collection of column expressions should be derived from the table that is the target of the INSERT, UPDATE, or DELETE. While Column objects are typical, the elements can also be expressions:
stmt = table.insert().returning(
(table.c.first_name + " " + table.c.last_name).
label('fullname'))Upon compilation, a RETURNING clause, or database equivalent, will be rendered within the statement. For INSERT and UPDATE, the values are the newly inserted/updated values. For DELETE, the values are those of the rows which were deleted.
Upon execution, the values of the columns to be returned are made available via the result set and can be iterated using ResultProxy.fetchone() and similar. For DBAPIs which do not natively support returning values (i.e. cx_oracle), SQLAlchemy will approximate this behavior at the result level so that a reasonable amount of behavioral neutrality is provided.
Note that not all databases/DBAPIs support RETURNING. For those backends with no support, an exception is raised upon compilation and/or execution. For those who do support it, the functionality across backends varies greatly, including restrictions on executemany() and other statements which return multiple rows. Please read the documentation notes for the database in use in order to determine the availability of RETURNING.
See also
ValuesBase.return_defaults() - an alternative method tailored towards efficient fetching of server-side defaults and triggers for single-row INSERTs or UPDATEs.
Compile and execute this Executable, returning the result’s scalar representation.
Apply a ‘grouping’ to this ClauseElement.
This method is overridden by subclasses to return a “grouping” construct, i.e. parenthesis. In particular it’s used by “binary” expressions to provide a grouping around themselves when placed into a larger expression, as well as by select() constructs when placed into the FROM clause of another select(). (Note that subqueries should be normally created using the Select.alias() method, as many platforms require nested SELECT statements to be named).
As expressions are composed together, the application of self_group() is automatic - end-user code should never need to use this method directly. Note that SQLAlchemy’s clause constructs take operator precedence into account - so parenthesis might not be needed, for example, in an expression like x OR (y AND z) - AND takes precedence over OR.
The base self_group() method of ClauseElement just returns self.
Return a copy with bindparam() elements replaced.
Same functionality as params(), except adds unique=True to affected bind parameters so that multiple statements can be used.
Add the given WHERE clause to a newly returned delete construct.
Add a table hint for a single table to this INSERT/UPDATE/DELETE statement.
Note
UpdateBase.with_hint() currently applies only to Microsoft SQL Server. For MySQL INSERT/UPDATE/DELETE hints, use UpdateBase.prefix_with().
The text of the hint is rendered in the appropriate location for the database backend in use, relative to the Table that is the subject of this statement, or optionally to that of the given Table passed as the selectable argument.
The dialect_name option will limit the rendering of a particular hint to a particular backend. Such as, to add a hint that only takes effect for SQL Server:
mytable.insert().with_hint("WITH (PAGLOCK)", dialect_name="mssql")New in version 0.7.6.
| Parameters: |
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|---|
Bases: sqlalchemy.sql.expression.ValuesBase
Represent an INSERT construct.
The Insert object is created using the insert() function.
See also
Construct a new Insert object.
This constructor is mirrored as a public API function; see insert() for a full usage and argument description.
Add a new kind of dialect-specific keyword argument for this class.
E.g.:
Index.argument_for("mydialect", "length", None)
some_index = Index('a', 'b', mydialect_length=5)The DialectKWArgs.argument_for() method is a per-argument way adding extra arguments to the DefaultDialect.construct_arguments dictionary. This dictionary provides a list of argument names accepted by various schema-level constructs on behalf of a dialect.
New dialects should typically specify this dictionary all at once as a data member of the dialect class. The use case for ad-hoc addition of argument names is typically for end-user code that is also using a custom compilation scheme which consumes the additional arguments.
| Parameters: |
|
|---|
New in version 0.9.4.
Return a ‘bind’ linked to this UpdateBase or a Table associated with it.
Compare this ClauseElement to the given ClauseElement.
Subclasses should override the default behavior, which is a straight identity comparison.
**kw are arguments consumed by subclass compare() methods and may be used to modify the criteria for comparison. (see ColumnElement)
Compile this SQL expression.
The return value is a Compiled object. Calling str() or unicode() on the returned value will yield a string representation of the result. The Compiled object also can return a dictionary of bind parameter names and values using the params accessor.
| Parameters: |
|
|---|
A collection of keyword arguments specified as dialect-specific options to this construct.
The arguments are present here in their original <dialect>_<kwarg> format. Only arguments that were actually passed are included; unlike the DialectKWArgs.dialect_options collection, which contains all options known by this dialect including defaults.
The collection is also writable; keys are accepted of the form <dialect>_<kwarg> where the value will be assembled into the list of options.
New in version 0.9.2.
Changed in version 0.9.4: The DialectKWArgs.dialect_kwargs collection is now writable.
See also
DialectKWArgs.dialect_options - nested dictionary form
A collection of keyword arguments specified as dialect-specific options to this construct.
This is a two-level nested registry, keyed to <dialect_name> and <argument_name>. For example, the postgresql_where argument would be locatable as:
arg = my_object.dialect_options['postgresql']['where']New in version 0.9.2.
See also
DialectKWArgs.dialect_kwargs - flat dictionary form
Compile and execute this Executable.
Set non-SQL options for the statement which take effect during execution.
Execution options can be set on a per-statement or per Connection basis. Additionally, the Engine and ORM Query objects provide access to execution options which they in turn configure upon connections.
The execution_options() method is generative. A new instance of this statement is returned that contains the options:
statement = select([table.c.x, table.c.y])
statement = statement.execution_options(autocommit=True)Note that only a subset of possible execution options can be applied to a statement - these include “autocommit” and “stream_results”, but not “isolation_level” or “compiled_cache”. See Connection.execution_options() for a full list of possible options.
Return a new Insert construct which represents an INSERT...FROM SELECT statement.
e.g.:
sel = select([table1.c.a, table1.c.b]).where(table1.c.c > 5)
ins = table2.insert().from_select(['a', 'b'], sel)| Parameters: |
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Warning
The inline=True flag should be set to True when using backends that support RETURNING, including Postgresql, Oracle, and SQL Server. This will prevent the implicit RETURNING clause from being appended to the statement, which is normally used to fetch the “last inserted primary key” value. This feature will raise an error if the statement inserts zero rows, and on some backends (e.g. Oracle) it will raise an error if the statement inserts more than one row.
insert.inline is set to True as follows:
sel = select([table1.c.a, table1.c.b]).where(table1.c.c > 5)
ins = table2.insert(inline=True).from_select(['a', 'b'], sel)Version 1.0 of SQLAlchemy will set this flag to True in all cases.
Note
Python-side and SQL function defaults, as described at Column Insert/Update Defaults, are not automatically included in the SELECT statement as rendered unless explicitly added to the statement. The behavior of automatically rendering these default values and expressions is available as of SQLAlchemy version 1.0.0.
New in version 0.8.3.
A synonym for DialectKWArgs.dialect_kwargs.
Set the parameters for the statement.
This method raises NotImplementedError on the base class, and is overridden by ValuesBase to provide the SET/VALUES clause of UPDATE and INSERT.
Add one or more expressions following the statement keyword, i.e. SELECT, INSERT, UPDATE, or DELETE. Generative.
This is used to support backend-specific prefix keywords such as those provided by MySQL.
E.g.:
stmt = table.insert().prefix_with("LOW_PRIORITY", dialect="mysql")Multiple prefixes can be specified by multiple calls to prefix_with().
| Parameters: |
|
|---|
Make use of a RETURNING clause for the purpose of fetching server-side expressions and defaults.
E.g.:
stmt = table.insert().values(data='newdata').return_defaults()
result = connection.execute(stmt)
server_created_at = result.returned_defaults['created_at']When used against a backend that supports RETURNING, all column values generated by SQL expression or server-side-default will be added to any existing RETURNING clause, provided that UpdateBase.returning() is not used simultaneously. The column values will then be available on the result using the ResultProxy.returned_defaults accessor as a dictionary, referring to values keyed to the Column object as well as its .key.
This method differs from UpdateBase.returning() in these ways:
ValuesBase.return_defaults() is used by the ORM to provide an efficient implementation for the eager_defaults feature of mapper().
| Parameters: | cols¶ – optional list of column key names or Column objects. If omitted, all column expressions evaulated on the server are added to the returning list. |
|---|
New in version 0.9.0.
Add a RETURNING or equivalent clause to this statement.
e.g.:
stmt = table.update().\
where(table.c.data == 'value').\
values(status='X').\
returning(table.c.server_flag,
table.c.updated_timestamp)
for server_flag, updated_timestamp in connection.execute(stmt):
print(server_flag, updated_timestamp)The given collection of column expressions should be derived from the table that is the target of the INSERT, UPDATE, or DELETE. While Column objects are typical, the elements can also be expressions:
stmt = table.insert().returning(
(table.c.first_name + " " + table.c.last_name).
label('fullname'))Upon compilation, a RETURNING clause, or database equivalent, will be rendered within the statement. For INSERT and UPDATE, the values are the newly inserted/updated values. For DELETE, the values are those of the rows which were deleted.
Upon execution, the values of the columns to be returned are made available via the result set and can be iterated using ResultProxy.fetchone() and similar. For DBAPIs which do not natively support returning values (i.e. cx_oracle), SQLAlchemy will approximate this behavior at the result level so that a reasonable amount of behavioral neutrality is provided.
Note that not all databases/DBAPIs support RETURNING. For those backends with no support, an exception is raised upon compilation and/or execution. For those who do support it, the functionality across backends varies greatly, including restrictions on executemany() and other statements which return multiple rows. Please read the documentation notes for the database in use in order to determine the availability of RETURNING.
See also
ValuesBase.return_defaults() - an alternative method tailored towards efficient fetching of server-side defaults and triggers for single-row INSERTs or UPDATEs.
Compile and execute this Executable, returning the result’s scalar representation.
Apply a ‘grouping’ to this ClauseElement.
This method is overridden by subclasses to return a “grouping” construct, i.e. parenthesis. In particular it’s used by “binary” expressions to provide a grouping around themselves when placed into a larger expression, as well as by select() constructs when placed into the FROM clause of another select(). (Note that subqueries should be normally created using the Select.alias() method, as many platforms require nested SELECT statements to be named).
As expressions are composed together, the application of self_group() is automatic - end-user code should never need to use this method directly. Note that SQLAlchemy’s clause constructs take operator precedence into account - so parenthesis might not be needed, for example, in an expression like x OR (y AND z) - AND takes precedence over OR.
The base self_group() method of ClauseElement just returns self.
Return a copy with bindparam() elements replaced.
Same functionality as params(), except adds unique=True to affected bind parameters so that multiple statements can be used.
specify a fixed VALUES clause for an INSERT statement, or the SET clause for an UPDATE.
Note that the Insert and Update constructs support per-execution time formatting of the VALUES and/or SET clauses, based on the arguments passed to Connection.execute(). However, the ValuesBase.values() method can be used to “fix” a particular set of parameters into the statement.
Multiple calls to ValuesBase.values() will produce a new construct, each one with the parameter list modified to include the new parameters sent. In the typical case of a single dictionary of parameters, the newly passed keys will replace the same keys in the previous construct. In the case of a list-based “multiple values” construct, each new list of values is extended onto the existing list of values.
| Parameters: |
|
|---|
See also
Inserts, Updates and Deletes - SQL Expression Language Tutorial
insert() - produce an INSERT statement
update() - produce an UPDATE statement
Add a table hint for a single table to this INSERT/UPDATE/DELETE statement.
Note
UpdateBase.with_hint() currently applies only to Microsoft SQL Server. For MySQL INSERT/UPDATE/DELETE hints, use UpdateBase.prefix_with().
The text of the hint is rendered in the appropriate location for the database backend in use, relative to the Table that is the subject of this statement, or optionally to that of the given Table passed as the selectable argument.
The dialect_name option will limit the rendering of a particular hint to a particular backend. Such as, to add a hint that only takes effect for SQL Server:
mytable.insert().with_hint("WITH (PAGLOCK)", dialect_name="mssql")New in version 0.7.6.
| Parameters: |
|
|---|
Bases: sqlalchemy.sql.expression.ValuesBase
Represent an Update construct.
The Update object is created using the update() function.
Construct a new Update object.
This constructor is mirrored as a public API function; see update() for a full usage and argument description.
Add a new kind of dialect-specific keyword argument for this class.
E.g.:
Index.argument_for("mydialect", "length", None)
some_index = Index('a', 'b', mydialect_length=5)The DialectKWArgs.argument_for() method is a per-argument way adding extra arguments to the DefaultDialect.construct_arguments dictionary. This dictionary provides a list of argument names accepted by various schema-level constructs on behalf of a dialect.
New dialects should typically specify this dictionary all at once as a data member of the dialect class. The use case for ad-hoc addition of argument names is typically for end-user code that is also using a custom compilation scheme which consumes the additional arguments.
| Parameters: |
|
|---|
New in version 0.9.4.
Return a ‘bind’ linked to this UpdateBase or a Table associated with it.
Compare this ClauseElement to the given ClauseElement.
Subclasses should override the default behavior, which is a straight identity comparison.
**kw are arguments consumed by subclass compare() methods and may be used to modify the criteria for comparison. (see ColumnElement)
Compile this SQL expression.
The return value is a Compiled object. Calling str() or unicode() on the returned value will yield a string representation of the result. The Compiled object also can return a dictionary of bind parameter names and values using the params accessor.
| Parameters: |
|
|---|
A collection of keyword arguments specified as dialect-specific options to this construct.
The arguments are present here in their original <dialect>_<kwarg> format. Only arguments that were actually passed are included; unlike the DialectKWArgs.dialect_options collection, which contains all options known by this dialect including defaults.
The collection is also writable; keys are accepted of the form <dialect>_<kwarg> where the value will be assembled into the list of options.
New in version 0.9.2.
Changed in version 0.9.4: The DialectKWArgs.dialect_kwargs collection is now writable.
See also
DialectKWArgs.dialect_options - nested dictionary form
A collection of keyword arguments specified as dialect-specific options to this construct.
This is a two-level nested registry, keyed to <dialect_name> and <argument_name>. For example, the postgresql_where argument would be locatable as:
arg = my_object.dialect_options['postgresql']['where']New in version 0.9.2.
See also
DialectKWArgs.dialect_kwargs - flat dictionary form
Compile and execute this Executable.
Set non-SQL options for the statement which take effect during execution.
Execution options can be set on a per-statement or per Connection basis. Additionally, the Engine and ORM Query objects provide access to execution options which they in turn configure upon connections.
The execution_options() method is generative. A new instance of this statement is returned that contains the options:
statement = select([table.c.x, table.c.y])
statement = statement.execution_options(autocommit=True)Note that only a subset of possible execution options can be applied to a statement - these include “autocommit” and “stream_results”, but not “isolation_level” or “compiled_cache”. See Connection.execution_options() for a full list of possible options.
A synonym for DialectKWArgs.dialect_kwargs.
Set the parameters for the statement.
This method raises NotImplementedError on the base class, and is overridden by ValuesBase to provide the SET/VALUES clause of UPDATE and INSERT.
Add one or more expressions following the statement keyword, i.e. SELECT, INSERT, UPDATE, or DELETE. Generative.
This is used to support backend-specific prefix keywords such as those provided by MySQL.
E.g.:
stmt = table.insert().prefix_with("LOW_PRIORITY", dialect="mysql")Multiple prefixes can be specified by multiple calls to prefix_with().
| Parameters: |
|
|---|
Make use of a RETURNING clause for the purpose of fetching server-side expressions and defaults.
E.g.:
stmt = table.insert().values(data='newdata').return_defaults()
result = connection.execute(stmt)
server_created_at = result.returned_defaults['created_at']When used against a backend that supports RETURNING, all column values generated by SQL expression or server-side-default will be added to any existing RETURNING clause, provided that UpdateBase.returning() is not used simultaneously. The column values will then be available on the result using the ResultProxy.returned_defaults accessor as a dictionary, referring to values keyed to the Column object as well as its .key.
This method differs from UpdateBase.returning() in these ways:
ValuesBase.return_defaults() is used by the ORM to provide an efficient implementation for the eager_defaults feature of mapper().
| Parameters: | cols¶ – optional list of column key names or Column objects. If omitted, all column expressions evaulated on the server are added to the returning list. |
|---|
New in version 0.9.0.
Add a RETURNING or equivalent clause to this statement.
e.g.:
stmt = table.update().\
where(table.c.data == 'value').\
values(status='X').\
returning(table.c.server_flag,
table.c.updated_timestamp)
for server_flag, updated_timestamp in connection.execute(stmt):
print(server_flag, updated_timestamp)The given collection of column expressions should be derived from the table that is the target of the INSERT, UPDATE, or DELETE. While Column objects are typical, the elements can also be expressions:
stmt = table.insert().returning(
(table.c.first_name + " " + table.c.last_name).
label('fullname'))Upon compilation, a RETURNING clause, or database equivalent, will be rendered within the statement. For INSERT and UPDATE, the values are the newly inserted/updated values. For DELETE, the values are those of the rows which were deleted.
Upon execution, the values of the columns to be returned are made available via the result set and can be iterated using ResultProxy.fetchone() and similar. For DBAPIs which do not natively support returning values (i.e. cx_oracle), SQLAlchemy will approximate this behavior at the result level so that a reasonable amount of behavioral neutrality is provided.
Note that not all databases/DBAPIs support RETURNING. For those backends with no support, an exception is raised upon compilation and/or execution. For those who do support it, the functionality across backends varies greatly, including restrictions on executemany() and other statements which return multiple rows. Please read the documentation notes for the database in use in order to determine the availability of RETURNING.
See also
ValuesBase.return_defaults() - an alternative method tailored towards efficient fetching of server-side defaults and triggers for single-row INSERTs or UPDATEs.
Compile and execute this Executable, returning the result’s scalar representation.
Apply a ‘grouping’ to this ClauseElement.
This method is overridden by subclasses to return a “grouping” construct, i.e. parenthesis. In particular it’s used by “binary” expressions to provide a grouping around themselves when placed into a larger expression, as well as by select() constructs when placed into the FROM clause of another select(). (Note that subqueries should be normally created using the Select.alias() method, as many platforms require nested SELECT statements to be named).
As expressions are composed together, the application of self_group() is automatic - end-user code should never need to use this method directly. Note that SQLAlchemy’s clause constructs take operator precedence into account - so parenthesis might not be needed, for example, in an expression like x OR (y AND z) - AND takes precedence over OR.
The base self_group() method of ClauseElement just returns self.
Return a copy with bindparam() elements replaced.
Same functionality as params(), except adds unique=True to affected bind parameters so that multiple statements can be used.
specify a fixed VALUES clause for an INSERT statement, or the SET clause for an UPDATE.
Note that the Insert and Update constructs support per-execution time formatting of the VALUES and/or SET clauses, based on the arguments passed to Connection.execute(). However, the ValuesBase.values() method can be used to “fix” a particular set of parameters into the statement.
Multiple calls to ValuesBase.values() will produce a new construct, each one with the parameter list modified to include the new parameters sent. In the typical case of a single dictionary of parameters, the newly passed keys will replace the same keys in the previous construct. In the case of a list-based “multiple values” construct, each new list of values is extended onto the existing list of values.
| Parameters: |
|
|---|
See also
Inserts, Updates and Deletes - SQL Expression Language Tutorial
insert() - produce an INSERT statement
update() - produce an UPDATE statement
return a new update() construct with the given expression added to its WHERE clause, joined to the existing clause via AND, if any.
Add a table hint for a single table to this INSERT/UPDATE/DELETE statement.
Note
UpdateBase.with_hint() currently applies only to Microsoft SQL Server. For MySQL INSERT/UPDATE/DELETE hints, use UpdateBase.prefix_with().
The text of the hint is rendered in the appropriate location for the database backend in use, relative to the Table that is the subject of this statement, or optionally to that of the given Table passed as the selectable argument.
The dialect_name option will limit the rendering of a particular hint to a particular backend. Such as, to add a hint that only takes effect for SQL Server:
mytable.insert().with_hint("WITH (PAGLOCK)", dialect_name="mssql")New in version 0.7.6.
| Parameters: |
|
|---|
Bases: sqlalchemy.sql.base.DialectKWArgs, sqlalchemy.sql.expression.HasPrefixes, sqlalchemy.sql.expression.Executable, sqlalchemy.sql.expression.ClauseElement
Form the base for INSERT, UPDATE, and DELETE statements.
x.__init__(...) initializes x; see help(type(x)) for signature
Add a new kind of dialect-specific keyword argument for this class.
E.g.:
Index.argument_for("mydialect", "length", None)
some_index = Index('a', 'b', mydialect_length=5)The DialectKWArgs.argument_for() method is a per-argument way adding extra arguments to the DefaultDialect.construct_arguments dictionary. This dictionary provides a list of argument names accepted by various schema-level constructs on behalf of a dialect.
New dialects should typically specify this dictionary all at once as a data member of the dialect class. The use case for ad-hoc addition of argument names is typically for end-user code that is also using a custom compilation scheme which consumes the additional arguments.
| Parameters: |
|
|---|
New in version 0.9.4.
Return a ‘bind’ linked to this UpdateBase or a Table associated with it.
Compare this ClauseElement to the given ClauseElement.
Subclasses should override the default behavior, which is a straight identity comparison.
**kw are arguments consumed by subclass compare() methods and may be used to modify the criteria for comparison. (see ColumnElement)
Compile this SQL expression.
The return value is a Compiled object. Calling str() or unicode() on the returned value will yield a string representation of the result. The Compiled object also can return a dictionary of bind parameter names and values using the params accessor.
| Parameters: |
|
|---|
A collection of keyword arguments specified as dialect-specific options to this construct.
The arguments are present here in their original <dialect>_<kwarg> format. Only arguments that were actually passed are included; unlike the DialectKWArgs.dialect_options collection, which contains all options known by this dialect including defaults.
The collection is also writable; keys are accepted of the form <dialect>_<kwarg> where the value will be assembled into the list of options.
New in version 0.9.2.
Changed in version 0.9.4: The DialectKWArgs.dialect_kwargs collection is now writable.
See also
DialectKWArgs.dialect_options - nested dictionary form
A collection of keyword arguments specified as dialect-specific options to this construct.
This is a two-level nested registry, keyed to <dialect_name> and <argument_name>. For example, the postgresql_where argument would be locatable as:
arg = my_object.dialect_options['postgresql']['where']New in version 0.9.2.
See also
DialectKWArgs.dialect_kwargs - flat dictionary form
Compile and execute this Executable.
Set non-SQL options for the statement which take effect during execution.
Execution options can be set on a per-statement or per Connection basis. Additionally, the Engine and ORM Query objects provide access to execution options which they in turn configure upon connections.
The execution_options() method is generative. A new instance of this statement is returned that contains the options:
statement = select([table.c.x, table.c.y])
statement = statement.execution_options(autocommit=True)Note that only a subset of possible execution options can be applied to a statement - these include “autocommit” and “stream_results”, but not “isolation_level” or “compiled_cache”. See Connection.execution_options() for a full list of possible options.
Return immediate child elements of this ClauseElement.
This is used for visit traversal.
**kwargs may contain flags that change the collection that is returned, for example to return a subset of items in order to cut down on larger traversals, or to return child items from a different context (such as schema-level collections instead of clause-level).
A synonym for DialectKWArgs.dialect_kwargs.
Set the parameters for the statement.
This method raises NotImplementedError on the base class, and is overridden by ValuesBase to provide the SET/VALUES clause of UPDATE and INSERT.
Add one or more expressions following the statement keyword, i.e. SELECT, INSERT, UPDATE, or DELETE. Generative.
This is used to support backend-specific prefix keywords such as those provided by MySQL.
E.g.:
stmt = table.insert().prefix_with("LOW_PRIORITY", dialect="mysql")Multiple prefixes can be specified by multiple calls to prefix_with().
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Add a RETURNING or equivalent clause to this statement.
e.g.:
stmt = table.update().\
where(table.c.data == 'value').\
values(status='X').\
returning(table.c.server_flag,
table.c.updated_timestamp)
for server_flag, updated_timestamp in connection.execute(stmt):
print(server_flag, updated_timestamp)The given collection of column expressions should be derived from the table that is the target of the INSERT, UPDATE, or DELETE. While Column objects are typical, the elements can also be expressions:
stmt = table.insert().returning(
(table.c.first_name + " " + table.c.last_name).
label('fullname'))Upon compilation, a RETURNING clause, or database equivalent, will be rendered within the statement. For INSERT and UPDATE, the values are the newly inserted/updated values. For DELETE, the values are those of the rows which were deleted.
Upon execution, the values of the columns to be returned are made available via the result set and can be iterated using ResultProxy.fetchone() and similar. For DBAPIs which do not natively support returning values (i.e. cx_oracle), SQLAlchemy will approximate this behavior at the result level so that a reasonable amount of behavioral neutrality is provided.
Note that not all databases/DBAPIs support RETURNING. For those backends with no support, an exception is raised upon compilation and/or execution. For those who do support it, the functionality across backends varies greatly, including restrictions on executemany() and other statements which return multiple rows. Please read the documentation notes for the database in use in order to determine the availability of RETURNING.
See also
ValuesBase.return_defaults() - an alternative method tailored towards efficient fetching of server-side defaults and triggers for single-row INSERTs or UPDATEs.
Compile and execute this Executable, returning the result’s scalar representation.
Apply a ‘grouping’ to this ClauseElement.
This method is overridden by subclasses to return a “grouping” construct, i.e. parenthesis. In particular it’s used by “binary” expressions to provide a grouping around themselves when placed into a larger expression, as well as by select() constructs when placed into the FROM clause of another select(). (Note that subqueries should be normally created using the Select.alias() method, as many platforms require nested SELECT statements to be named).
As expressions are composed together, the application of self_group() is automatic - end-user code should never need to use this method directly. Note that SQLAlchemy’s clause constructs take operator precedence into account - so parenthesis might not be needed, for example, in an expression like x OR (y AND z) - AND takes precedence over OR.
The base self_group() method of ClauseElement just returns self.
Return a copy with bindparam() elements replaced.
Same functionality as params(), except adds unique=True to affected bind parameters so that multiple statements can be used.
Add a table hint for a single table to this INSERT/UPDATE/DELETE statement.
Note
UpdateBase.with_hint() currently applies only to Microsoft SQL Server. For MySQL INSERT/UPDATE/DELETE hints, use UpdateBase.prefix_with().
The text of the hint is rendered in the appropriate location for the database backend in use, relative to the Table that is the subject of this statement, or optionally to that of the given Table passed as the selectable argument.
The dialect_name option will limit the rendering of a particular hint to a particular backend. Such as, to add a hint that only takes effect for SQL Server:
mytable.insert().with_hint("WITH (PAGLOCK)", dialect_name="mssql")New in version 0.7.6.
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Bases: sqlalchemy.sql.expression.UpdateBase
Supplies support for ValuesBase.values() to INSERT and UPDATE constructs.
Make use of a RETURNING clause for the purpose of fetching server-side expressions and defaults.
E.g.:
stmt = table.insert().values(data='newdata').return_defaults()
result = connection.execute(stmt)
server_created_at = result.returned_defaults['created_at']When used against a backend that supports RETURNING, all column values generated by SQL expression or server-side-default will be added to any existing RETURNING clause, provided that UpdateBase.returning() is not used simultaneously. The column values will then be available on the result using the ResultProxy.returned_defaults accessor as a dictionary, referring to values keyed to the Column object as well as its .key.
This method differs from UpdateBase.returning() in these ways:
ValuesBase.return_defaults() is used by the ORM to provide an efficient implementation for the eager_defaults feature of mapper().
| Parameters: | cols¶ – optional list of column key names or Column objects. If omitted, all column expressions evaulated on the server are added to the returning list. |
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New in version 0.9.0.
specify a fixed VALUES clause for an INSERT statement, or the SET clause for an UPDATE.
Note that the Insert and Update constructs support per-execution time formatting of the VALUES and/or SET clauses, based on the arguments passed to Connection.execute(). However, the ValuesBase.values() method can be used to “fix” a particular set of parameters into the statement.
Multiple calls to ValuesBase.values() will produce a new construct, each one with the parameter list modified to include the new parameters sent. In the typical case of a single dictionary of parameters, the newly passed keys will replace the same keys in the previous construct. In the case of a list-based “multiple values” construct, each new list of values is extended onto the existing list of values.
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See also
Inserts, Updates and Deletes - SQL Expression Language Tutorial
insert() - produce an INSERT statement
update() - produce an UPDATE statement