All components are derived from a common base class ClauseElement. Common behaviors are organized based on class hierarchies, in some cases via mixins.

All object construction from this package occurs via functions which in some cases will construct composite ClauseElement structures together, and in other cases simply return a single ClauseElement constructed directly. The function interface affords a more "DSL-ish" feel to constructing SQL expressions and also allows future class reorganizations.

Even though classes are not constructed directly from the outside, most classes which have additional public methods are considered to be public (i.e. have no leading underscore). Other classes which are "semi-public" are marked with a single leading underscore; these classes usually have few or no public methods and are less guaranteed to stay the same in future releases.

Module Functions

def alias(selectable, alias=None)

Return an Alias object.

An Alias represents any FromClause with an alternate name assigned within SQL, typically using the AS clause when generated, e.g. SELECT * FROM table AS aliasname.

Similar functionality is available via the alias() method available on all FromClause subclasses.

selectable

any FromClause subclass, such as a table, select statement, etc..

alias

string name to be assigned as the alias. If None, a random name will be generated.

def and_(*clauses)

Join a list of clauses together using the AND operator.

The & operator is also overloaded on all _CompareMixin subclasses to produce the same result.

def asc(column)

Return an ascending ORDER BY clause element.

E.g.:

order_by = [asc(table1.mycol)]

def between(ctest, cleft, cright)

Return a BETWEEN predicate clause.

Equivalent of SQL clausetest BETWEEN clauseleft AND clauseright.

The between() method on all _CompareMixin subclasses provides similar functionality.

def between_(*args, **kwargs)

synonym for between() (deprecated).

def bindparam(key, value=None, type=None, shortname=None, unique=False)

Create a bind parameter clause with the given key.

value: a default value for this bind parameter. a bindparam with a value is called a value-based bindparam.
shortname: an alias for this bind parameter. usually used to alias the key and label of a column, i.e. somecolname and sometable_somecolname
type: a sqlalchemy.types.TypeEngine object indicating the type of this bind param, will invoke type-specific bind parameter processing
unique: if True, bind params sharing the same name will have their underlying key modified to a uniquely generated name. mostly useful with value-based bind params.

def case(whens, value=None, else_=None)

Produce a CASE statement.

whens: A sequence of pairs to be translated into "when / then" clauses.
value: Optional for simple case statements.
else_: Optional as well, for case defaults.

def cast(clause, totype, **kwargs)

Return a CAST function.

Equivalent of SQL CAST(clause AS totype).

Use with a TypeEngine subclass, i.e:

cast(table.c.unit_price * table.c.qty, Numeric(10,4))

or:

cast(table.c.timestamp, DATE)

def column(text, type=None)

Return a textual column clause, as would be in the columns clause of a SELECT statement.

The object returned is an instance of _ColumnClause, which represents the "syntactical" portion of the schema-level Column object.

text

the name of the column. Quoting rules will be applied to the clause like any other column name. For textual column constructs that are not to be quoted, use the literal_column() function.

type

an optional TypeEngine object which will provide result-set translation for this column.

def delete(table, whereclause=None, **kwargs)

Return a _Delete clause element.

Similar functionality is available via the delete() method on Table.

table

The table to be updated.

whereclause

A ClauseElement describing the WHERE condition of the UPDATE statement.

def desc(column)

Return a descending ORDER BY clause element.

E.g.:

order_by = [desc(table1.mycol)]

def distinct(expr)

return a DISTINCT clause.

def except_(*selects, **kwargs)

Return an EXCEPT of multiple selectables.

The returned object is an instance of CompoundSelect.

*selects

a list of Select instances.

**kwargs

available keyword arguments are the same as those of select().

def except_all(*selects, **kwargs)

Return an EXCEPT ALL of multiple selectables.

The returned object is an instance of CompoundSelect.

*selects

a list of Select instances.

**kwargs

available keyword arguments are the same as those of select().

def exists(*args, **kwargs)

Return an EXISTS clause as applied to a Select object.

The resulting _Exists object can be executed by itself or used as a subquery within an enclosing select.

*args, **kwargs

all arguments are sent directly to the select() function to produce a SELECT statement.

def extract(field, expr)

Return the clause extract(field FROM expr).

def insert(table, values=None, **kwargs)

Return an _Insert clause element.

Similar functionality is available via the insert() method on Table.

table

The table to be inserted into.

values

A dictionary which specifies the column specifications of the INSERT, and is optional. If left as None, the column specifications are determined from the bind parameters used during the compile phase of the INSERT statement. If the bind parameters also are None during the compile phase, then the column specifications will be generated from the full list of table columns.

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:

a literal data value (i.e. string, number, etc.);
a Column object;
a SELECT statement.

If a SELECT statement is specified which references this INSERT statement's table, the statement will be correlated against the INSERT statement.

def intersect(*selects, **kwargs)

Return an INTERSECT of multiple selectables.

The returned object is an instance of CompoundSelect.

*selects

a list of Select instances.

**kwargs

available keyword arguments are the same as those of select().

def intersect_all(*selects, **kwargs)

Return an INTERSECT ALL of multiple selectables.

The returned object is an instance of CompoundSelect.

*selects

a list of Select instances.

**kwargs

available keyword arguments are the same as those of select().

def is_column(col)

def join(left, right, onclause=None, **kwargs)

Return a JOIN clause element (regular inner join).

The returned object is an instance of Join.

Similar functionality is also available via the join() method on any FromClause.

left

The left side of the join.

right

The right side of the join.

onclause

Optional criterion for the ON clause, is derived from foreign key relationships established between left and right otherwise.

To chain joins together, use the join() or outerjoin() methods on the resulting Join object.

def label(name, obj)

Return a _Label object for the given ColumnElement.

A label changes the name of an element in the columns clause of a SELECT statement, typically via the AS SQL keyword.

This functionality is more conveniently available via the label() method on ColumnElement.

name

label name

obj

a ColumnElement.

def literal(value, type=None)

Return a literal clause, bound to a bind parameter.

Literal clauses are created automatically when non- ClauseElement objects (such as strings, ints, dates, etc.) are used in a comparison operation with a _CompareMixin subclass, such as a Column object. Use this function to force the generation of a literal clause, which will be created as a _BindParamClause with a bound value.

value

the value to be bound. can be any Python object supported by the underlying DBAPI, or is translatable via the given type argument.

type

an optional TypeEngine which will provide bind-parameter translation for this literal.

def literal_column(text, type=None)

Return a textual column clause, as would be in the columns clause of a SELECT statement.

The object returned is an instance of _ColumnClause, which represents the "syntactical" portion of the schema-level Column object.

text

the name of the column. Quoting rules will not be applied to the column. For textual column constructs that should be quoted like any other column construct, use the column() function.

type

an optional TypeEngine object which will provide result-set translation for this column.

def not_(clause)

Return a negation of the given clause, i.e. NOT(clause).

The ~ operator is also overloaded on all _CompareMixin subclasses to produce the same result.

def null()

Return a _Null object, which compiles to NULL in a sql statement.

def or_(*clauses)

Join a list of clauses together using the OR operator.

The | operator is also overloaded on all _CompareMixin subclasses to produce the same result.

def outerjoin(left, right, onclause=None, **kwargs)

Return an OUTER JOIN clause element.

The returned object is an instance of Join.

Similar functionality is also available via the outerjoin() method on any FromClause.

left

The left side of the join.

right

The right side of the join.

onclause

Optional criterion for the ON clause, is derived from foreign key relationships established between left and right otherwise.

To chain joins together, use the join() or outerjoin() methods on the resulting Join object.

def select(columns=None, whereclause=None, from_obj=[], **kwargs)

Returns a SELECT clause element.

Similar functionality is also available via the select() method on any FromClause.

The returned object is an instance of Select.

All arguments which accept ClauseElement arguments also accept string arguments, which will be converted as appropriate into either text() or literal_column() constructs.

columns

A list of ClauseElement objects, typically ColumnElement objects or subclasses, which will form the columns clause of the resulting statement. For all members which are instances of Selectable, the individual ColumnElement members of the Selectable will be added individually to the columns clause. For example, specifying a Table instance will result in all the contained Column objects within to be added to the columns clause.

This argument is not present on the form of select() available on Table.

whereclause

A ClauseElement expression which will be used to form the WHERE clause.

from_obj

A list of ClauseElement objects which will be added to the FROM clause of the resulting statement. Note that "from" objects are automatically located within the columns and whereclause ClauseElements. Use this parameter to explicitly specify "from" objects which are not automatically locatable. This could include Table objects that aren't otherwise present, or Join objects whose presence will supercede that of the Table objects already located in the other clauses.

**kwargs

Additional parameters include:

order_by

a scalar or list of ClauseElement objects which will comprise the ORDER BY clause of the resulting select.

group_by

a list of ClauseElement objects which will comprise the GROUP BY clause of the resulting select.

having

a ClauseElement that will comprise the HAVING clause of the resulting select when GROUP BY is used.

use_labels=False

when True, the statement will be generated using labels for each column in the columns clause, which qualify each column with its parent table's (or aliases) name so that name conflicts between columns in different tables don't occur. The format of the label is <tablename>_<column>. The "c" collection of the resulting Select object will use these names as well for targeting column members.

distinct=False

when True, applies a DISTINCT qualifier to the columns clause of the resulting statement.

for_update=False

when True, applies FOR UPDATE to the end of the resulting statement. Certain database dialects also support alternate values for this parameter, for example mysql supports "read" which translates to LOCK IN SHARE MODE, and oracle supports "nowait" which translates to FOR UPDATE NOWAIT.

bind=None

an Engine or Connection instance to which the resulting Select object will be bound. The Select object will otherwise automatically bind to whatever Connectable instances can be located within its contained ClauseElement members.

engine=None

deprecated. a synonym for "bind".

limit=None

a numerical value which usually compiles to a LIMIT expression in the resulting select. Databases that don't support LIMIT will attempt to provide similar functionality.

offset=None

a numerical value which usually compiles to an OFFSET expression in the resulting select. Databases that don't support OFFSET will attempt to provide similar functionality.

scalar=False

when True, indicates that the resulting Select object is to be used in the "columns" clause of another select statement, where the evaluated value of the column is the scalar result of this statement. Normally, placing any Selectable within the columns clause of a select() call will expand the member columns of the Selectable individually.

correlate=True

indicates that this Select object should have its contained FromClause elements "correlated" to an enclosing Select object. This means that any ClauseElement instance within the "froms" collection of this Select which is also present in the "froms" collection of an enclosing select will not be rendered in the FROM clause of this select statement.

def subquery(alias, *args, **kwargs)

Return an Alias object derived from a Select.

name: alias name
*args, **kwargs: all other arguments are delivered to the select() function.

def table(name, *columns)

Return a Table object.

This is a primitive version of the Table object, which is a subclass of this object.

def text(text, bind=None, engine=None, *args, **kwargs)

Create literal text to be inserted into a query.

When constructing a query from a select(), update(), insert() or delete(), using plain strings for argument values will usually result in text objects being created automatically. Use this function when creating textual clauses outside of other ClauseElement objects, or optionally wherever plain text is to be used.

text

The text of the SQL statement to be created. use :<param> to specify bind parameters; they will be compiled to their engine-specific format.

bind

An optional connection or engine to be used for this text query.

engine

deprecated. a synonym for 'bind'.

bindparams

A list of bindparam() instances which can be used to define the types and/or initial values for the bind parameters within the textual statement; the keynames of the bindparams must match those within the text of the statement. The types will be used for pre-processing on bind values.

typemap

A dictionary mapping the names of columns represented in the SELECT clause of the textual statement to type objects, which will be used to perform post-processing on columns within the result set (for textual statements that produce result sets).

def union(*selects, **kwargs)

Return a UNION of multiple selectables.

The returned object is an instance of CompoundSelect.

A similar union() method is available on all FromClause subclasses.

*selects

a list of Select instances.

**kwargs

available keyword arguments are the same as those of select().

def union_all(*selects, **kwargs)

Return a UNION ALL of multiple selectables.

The returned object is an instance of CompoundSelect.

A similar union_all() method is available on all FromClause subclasses.

*selects

a list of Select instances.

**kwargs

available keyword arguments are the same as those of select().

def update(table, whereclause=None, values=None, **kwargs)

Return an _Update clause element.

Similar functionality is available via the update() method on Table.

table

The table to be updated.

whereclause

A ClauseElement describing the WHERE condition of the UPDATE statement.

values

A dictionary which specifies the SET conditions of the UPDATE, and is optional. If left as None, the SET conditions are determined from the bind parameters used during the compile phase of the UPDATE statement. If the bind parameters also are None during the compile phase, then the SET conditions will be generated from the full list of table columns.

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:

a literal data value (i.e. string, number, etc.);
a Column object;
a SELECT statement.

If a SELECT statement is specified which references this UPDATE statement's table, the statement will be correlated against the UPDATE statement.

class AbstractDialect(object)

Represent the behavior of a particular database.

Used by Compiled objects.

back to section top

class Alias(FromClause)

represent an alias, as typically applied to any table or sub-select within a SQL statement using the AS keyword (or without the keyword on certain databases such as Oracle).

this object is constructed from the alias() module level function as well as the alias() method available on all FromClause subclasses.

def __init__(self, selectable, alias=None)

Construct a new Alias.

def accept_visitor(self, visitor)

bind = property()

engine = property()

def get_children(self, **kwargs)

def named_with_column(self)

def supports_execution(self)

back to section top

class _BinaryExpression(ColumnElement)

Represent an expression that is LEFT <operator> RIGHT.

def __init__(self, left, right, operator, type=None, negate=None)

Construct a new _BinaryExpression.

def accept_visitor(self, visitor)

def compare(self, other)

Compare this _BinaryExpression against the given _BinaryExpression.

def copy_container(self)

def get_children(self, **kwargs)

def self_group(self, against=None)

back to section top

class _BindParamClause(ClauseElement,_CompareMixin)

Represent a bind parameter.

Public constructor is the bindparam() function.

def __init__(self, key, value, shortname=None, type=None, unique=False)

Construct a _BindParamClause.

key: the key for this bind param. Will be used in the generated SQL statement for dialects that use named parameters. This value may be modified when part of a compilation operation, if other _BindParamClause objects exist with the same key, or if its length is too long and truncation is required.
value: Initial value for this bind param. This value may be overridden by the dictionary of parameters sent to statement compilation/execution.
shortname: Defaults to the key, a short name that will also identify this bind parameter, similar to an alias. the bind parameter keys sent to a statement compilation or compiled execution may match either the key or the shortname of the corresponding _BindParamClause objects.
type: A TypeEngine object that will be used to pre-process the value corresponding to this _BindParamClause at execution time.
unique: if True, the key name of this BindParamClause will be modified if another _BindParamClause of the same name already has been located within the containing ClauseElement.

def accept_visitor(self, visitor)

def compare(self, other)

Compare this _BindParamClause to the given clause.

Since compare() is meant to compare statement syntax, this method returns True if the two _BindParamClauses have just the same type.

def copy_container(self)

def typeprocess(self, value, dialect)

back to section top

class _CalculatedClause(ColumnElement)

Describe a calculated SQL expression that has a type, like CASE.

Extends ColumnElement to provide column-level comparison operators.

def __init__(self, name, *clauses, **kwargs)

Construct a new _CalculatedClause.

def accept_visitor(self, visitor)

def copy_container(self)

def execute(self)

def get_children(self, **kwargs)

key = property()

def scalar(self)

def select(self)

back to section top

class _Cast(ColumnElement)

def __init__(self, clause, totype, **kwargs)

Construct a new _Cast.

def accept_visitor(self, visitor)

def get_children(self, **kwargs)

back to section top

class ClauseElement(object)

Base class for elements of a programmatically constructed SQL expression.

def accept_visitor(self, visitor)

Accept a ClauseVisitor and call the appropriate visit_xxx method.

bind = property()

Returns the Engine or Connection to which this ClauseElement is bound, or None if none found.

def compare(self, other)

Compare this ClauseElement to the given ClauseElement.

Subclasses should override the default behavior, which is a straight identity comparison.

def compile(self, bind=None, engine=None, parameters=None, compiler=None, dialect=None)

Compile this SQL expression.

Uses the given Compiler, or the given AbstractDialect or Engine to create a Compiler. If no compiler arguments are given, tries to use the underlying Engine this ClauseElement is bound to to create a Compiler, if any.

Finally, if there is no bound Engine, uses an ANSIDialect to create a default Compiler.

parameters is a dictionary representing the default bind parameters to be used with the statement. If parameters is a list, it is assumed to be a list of dictionaries and the first dictionary in the list is used with which to compile against.

The bind parameters can in some cases determine the output of the compilation, such as for UPDATE and INSERT statements the bind parameters that are present determine the SET and VALUES clause of those statements.

def copy_container(self)

Return a copy of this ClauseElement, if this ClauseElement contains other ClauseElements.

If this ClauseElement is not a container, it should return self. This is used to create copies of expression trees that still reference the same leaf nodes. The new structure can then be restructured without affecting the original.

engine = property()

Returns the Engine or Connection to which this ClauseElement is bound, or None if none found.

def execute(self, *multiparams, **params)

Compile and execute this ClauseElement.

def get_children(self, **kwargs)

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).

def scalar(self, *multiparams, **params)

Compile and execute this ClauseElement, returning the result's scalar representation.

def self_group(self, against=None)

def supports_execution(self)

Return True if this clause element represents a complete executable statement.

def __and__(self, other)

def __invert__(self)

def __or__(self, other)

back to section top

class ClauseList(ClauseElement)

Describe a list of clauses, separated by an operator.

By default, is comma-separated, such as a column listing.

def __init__(self, *clauses, **kwargs)

Construct a new ClauseList.

def accept_visitor(self, visitor)

def append(self, clause)

def compare(self, other)

Compare this ClauseList to the given ClauseList, including a comparison of all the clause items.

def copy_container(self)

def get_children(self, **kwargs)

def self_group(self, against=None)

def __iter__(self)

def __len__(self)

back to section top

class ClauseParameters(object)

Represent a dictionary/iterator of bind parameter key names/values.

Tracks the original _BindParamClause objects as well as the keys/position of each parameter, and can return parameters as a dictionary or a list. Will process parameter values according to the TypeEngine objects present in the _BindParamClause instances.

def __init__(self, dialect, positional=None)

Construct a new ClauseParameters.

def get_original(self, key)

Return the given parameter as it was originally placed in this ClauseParameters object, without any Type conversion.

def get_original_dict(self)

def get_processed(self, key)

def get_raw_dict(self)

def get_raw_list(self)

def keys(self)

def set_parameter(self, bindparam, value, name)

def set_value(self, key, value)

def __contains__(self, key)

def __getitem__(self, key)

back to section top

class ClauseVisitor(object)

A class that knows how to traverse and visit ClauseElements.

Each ClauseElement's accept_visitor() method will call a corresponding visit_XXXX() method here. Traversal of a hierarchy of ClauseElements is achieved via the traverse() method, which is passed the lead ClauseElement.

By default, ClauseVisitor traverses all elements fully. Options can be specified at the class level via the __traverse_options__ dictionary which will be passed to the get_children() method of each ClauseElement; these options can indicate modifications to the set of elements returned, such as to not return column collections (column_collections=False) or to return Schema-level items (schema_visitor=True).

def chain(self, visitor)

'chain' an additional ClauseVisitor onto this ClauseVisitor.

the chained visitor will receive all visit events after this one.

def traverse(self, obj, stop_on=None)

def visit_alias(self, alias)

def visit_binary(self, binary)

def visit_bindparam(self, bindparam)

def visit_calculatedclause(self, calcclause)

def visit_cast(self, cast)

def visit_clauselist(self, list)

def visit_column(self, column)

def visit_compound(self, compound)

def visit_compound_select(self, compound)

def visit_fromclause(self, fromclause)

def visit_function(self, func)

def visit_grouping(self, gr)

def visit_join(self, join)

def visit_label(self, label)

def visit_null(self, null)

def visit_select(self, select)

def visit_table(self, table)

def visit_textclause(self, textclause)

def visit_typeclause(self, typeclause)

def visit_unary(self, unary)

back to section top

class _ColumnClause(ColumnElement)

Represents a generic column expression from any textual string. This includes columns associated with tables, aliases and select statements, but also any arbitrary text. May or may not be bound to an underlying Selectable. _ColumnClause is usually created publically via the column() function or the column_literal() function.

text

the text of the element.

selectable

parent selectable.

type

TypeEngine object which can associate this _ColumnClause with a type.

case_sensitive

defines whether identifier quoting rules will be applied to the generated text of this _ColumnClause so that it is identified in a case-sensitive manner.

is_literal

if True, the _ColumnClause is assumed to be an exact expression that will be delivered to the output with no quoting rules applied regardless of case sensitive settings. the column_literal() function is usually used to create such a _ColumnClause.

def __init__(self, text, selectable=None, type=None, _is_oid=False, case_sensitive=True, is_literal=False)

Construct a new _ColumnClause.

def accept_visitor(self, visitor)

is_labeled = property()

def label(self, name)

back to section top

class ColumnCollection(OrderedProperties)

An ordered dictionary that stores a list of ColumnElement instances.

Overrides the __eq__() method to produce SQL clauses between sets of correlated columns.

def __init__(self, *cols)

Construct a new ColumnCollection.

def add(self, column)

Add a column to this collection.

The key attribute of the column will be used as the hash key for this dictionary.

def contains_column(self, col)

def extend(self, iter)

def remove(self, column)

def __contains__(self, col)

def __eq__(self, other)

back to section top

class ColumnElement(Selectable,_CompareMixin)

Represent an element that is useable within the "column clause" portion of a SELECT statement.

This includes columns associated with tables, aliases, and subqueries, expressions, function calls, SQL keywords such as NULL, literals, etc. ColumnElement is the ultimate base class for all such elements.

ColumnElement supports the ability to be a proxy element, which indicates that the ColumnElement may be associated with a Selectable which was derived from another Selectable. An example of a "derived" Selectable is an Alias of a Table.

a ColumnElement, by subclassing the _CompareMixin mixin class, provides the ability to generate new ClauseElement objects using Python expressions. See the _CompareMixin docstring for more details.

columns = property()

Columns accessor which returns self, to provide compatibility with Selectable objects.

foreign_key = property()

foreign_keys = property()

Foreign key accessor. References a list of ForeignKey objects which each represent a foreign key placed on this column's ultimate ancestor.

orig_set = property()

A Set containing TableClause-bound, non-proxied ColumnElements for which this ColumnElement is a proxy. In all cases except for a column proxied from a Union (i.e. CompoundSelect), this set will be just one element.

primary_key = property()

Primary key flag. Indicates if this Column represents part or whole of a primary key for its parent table.

def shares_lineage(self, othercolumn)

Return True if the given ColumnElement has a common ancestor to this ColumnElement.

back to section top

class ColumnSet(OrderedSet)

def contains_column(self, col)

def extend(self, cols)

def __add__(self, other)

def __eq__(self, other)

back to section top

class _CompareMixin(object)

Defines comparison operations for ClauseElement instances.

This is a mixin class that adds the capability to produce ClauseElement instances based on regular Python operators. These operations are achieved using Python's operator overload methods (i.e. __eq__(), __ne__(), etc.

Overridden operators include all comparison operators (i.e. '==', '!=', '<'), math operators ('+', '-', '*', etc), the '&' and '|' operators which evaluate to AND and OR respectively.

Other methods exist to create additional SQL clauses such as IN, LIKE, DISTINCT, etc.

def between(self, cleft, cright)

produce a BETWEEN clause, i.e. <column> BETWEEN <cleft> AND <cright>

def distinct(self)

produce a DISTINCT clause, i.e. DISTINCT <columnname>

def endswith(self, other)

produce the clause LIKE '%<other>'

def in_(self, *other)

produce an IN clause.

def label(self, name)

produce a column label, i.e. <columnname> AS <name>

def like(self, other)

produce a LIKE clause.

def op(self, operator)

produce a generic operator function.

e.g.

somecolumn.op("*")(5)

produces

somecolumn * 5

operator: a string which will be output as the infix operator between this ClauseElement and the expression passed to the generated function.

def startswith(self, other)

produce the clause LIKE '<other>%'

def __add__(self, other)

def __div__(self, other)

def __eq__(self, other)

def __ge__(self, other)

def __gt__(self, other)

def __le__(self, other)

def __lt__(self, other)

def __mod__(self, other)

def __mul__(self, other)

def __ne__(self, other)

def __radd__(self, other)

def __rdiv__(self, other)

def __rmul__(self, other)

def __rsub__(self, other)

def __sub__(self, other)

def __truediv__(self, other)

back to section top

class Compiled(ClauseVisitor)

Represent a compiled SQL expression.

The __str__ method of the Compiled object should produce the actual text of the statement. Compiled objects are specific to their underlying database dialect, and also may or may not be specific to the columns referenced within a particular set of bind parameters. In no case should the Compiled object be dependent on the actual values of those bind parameters, even though it may reference those values as defaults.

def __init__(self, dialect, statement, parameters, bind=None, engine=None)

Construct a new Compiled object.

statement: ClauseElement to be compiled.
parameters: Optional dictionary indicating a set of bind parameters specified with this Compiled object. These parameters are the default values corresponding to the ClauseElement's _BindParamClauses when the Compiled is executed. In the case of an INSERT or UPDATE statement, these parameters will also result in the creation of new _BindParamClause objects for each key and will also affect the generated column list in an INSERT statement and the SET clauses of an UPDATE statement. The keys of the parameter dictionary can either be the string names of columns or _ColumnClause objects.
bind: optional engine or connection which will be bound to the compiled object.
engine: deprecated, a synonym for 'bind'

def compile(self)

def construct_params(self, params)

Return the bind params for this compiled object.

Will start with the default parameters specified when this Compiled object was first constructed, and will override those values with those sent via **params, which are key/value pairs. Each key should match one of the _BindParamClause objects compiled into this object; either the key or shortname property of the _BindParamClause.

def execute(self, *multiparams, **params)

Execute this compiled object.

def get_params(self, **params)

Deprecated. use construct_params(). (supports unicode names)

def scalar(self, *multiparams, **params)

Execute this compiled object and return the result's scalar value.

back to section top

class CompoundSelect(_SelectBaseMixin,FromClause)

def __init__(self, keyword, *selects, **kwargs)

Construct a new CompoundSelect.

def accept_visitor(self, visitor)

def get_children(self, column_collections=True, **kwargs)

name = property()

def self_group(self, against=None)

back to section top

class _Delete(_UpdateBase)

def __init__(self, table, whereclause)

Construct a new _Delete.

def accept_visitor(self, visitor)

def get_children(self, **kwargs)

back to section top

class Executor(object)

Interface representing a "thing that can produce Compiled objects and execute them".

def compiler(self, statement, parameters, **kwargs)

Return a Compiled object for the given statement and parameters.

def execute_compiled(self, compiled, parameters, echo=None, **kwargs)

Execute a Compiled object.

back to section top

class _Exists(_UnaryExpression)

def __init__(self, *args, **kwargs)

Construct a new _Exists.

back to section top

class FromClause(Selectable)

Represent an element that can be used within the FROM clause of a SELECT statement.

def __init__(self, name=None)

Construct a new FromClause.

def accept_visitor(self, visitor)

def alias(self, name=None)

c = property()

columns = property()

def corresponding_column(self, column, raiseerr=True, keys_ok=False, require_embedded=False)

Given a ColumnElement, return the exported ColumnElement object from this Selectable which corresponds to that original Column via a common anscestor column.

column: the target ColumnElement to be matched
raiseerr: if True, raise an error if the given ColumnElement could not be matched. if False, non-matches will return None.
keys_ok: if the ColumnElement cannot be matched, attempt to match based on the string "key" property of the column alone. This makes the search much more liberal.
require_embedded: only return corresponding columns for the given ColumnElement, if the given ColumnElement is actually present within a sub-element of this FromClause. Normally the column will match if it merely shares a common anscestor with one of the exported columns of this FromClause.

def count(self, whereclause=None, **params)

def default_order_by(self)

foreign_keys = property()

def join(self, right, *args, **kwargs)

def named_with_column(self)

True if the name of this FromClause may be prepended to a column in a generated SQL statement.

oid_column = property()

original_columns = property()

A dictionary mapping an original Table-bound column to a proxied column in this FromClause.

def outerjoin(self, right, *args, **kwargs)

primary_key = property()

back to section top

class _Function(_CalculatedClause,FromClause)

Describe a SQL function.

Extends _CalculatedClause, turn the clauselist into function arguments, also adds a packagenames argument.

def __init__(self, name, *clauses, **kwargs)

Construct a new _Function.

def accept_visitor(self, visitor)

def append(self, clause)

def copy_container(self)

key = property()

back to section top

class _FunctionGenerator(object)

Generate _Function objects based on getattr calls.

def __init__(self, **opts)

Construct a new _FunctionGenerator.

def __call__(self, *c, **kwargs)

def __getattr__(self, name)

back to section top

class _Grouping(ColumnElement)

def __init__(self, elem)

Construct a new _Grouping.

def accept_visitor(self, visitor)

def copy_container(self)

def get_children(self, **kwargs)

key = property()

orig_set = property()

def __getattr__(self, attr)

back to section top

class _Insert(_UpdateBase)

def __init__(self, table, values=None)

Construct a new _Insert.

def accept_visitor(self, visitor)

def get_children(self, **kwargs)

back to section top

class Join(FromClause)

represent a JOIN construct between two FromClause elements.

the public constructor function for Join is the module-level join() function, as well as the join() method available off all FromClause subclasses.

def __init__(self, left, right, onclause=None, isouter=False)

Construct a new Join.

def accept_visitor(self, visitor)

def alias(self, name=None)

Create a Select out of this Join clause and return an Alias of it.

The Select is not correlating.

encodedname = property()

engine = property()

folded_equivalents = property()

Returns the column list of this Join with all equivalently-named, equated columns folded into one column, where 'equated' means they are equated to each other in the ON clause of this join.

def get_children(self, **kwargs)

name = property()

primary_key = property()

def select(self, whereclause=None, fold_equivalents=False, **kwargs)

Create a Select from this Join.

whereclause: the WHERE criterion that will be sent to the select() function
fold_equivalents: based on the join criterion of this Join, do not include repeat column names in the column list of the resulting select, for columns that are calculated to be "equivalent" based on the join criterion of this Join. this will recursively apply to any joins directly nested by this one as well.
**kwargs: all other kwargs are sent to the underlying select() function. See the select() module level function for details.

back to section top

class _Label(ColumnElement)

represent a label, as typically applied to any column-level element using the AS sql keyword.

this object is constructed from the label() module level function as well as the label() method available on all ColumnElement subclasses.

def __init__(self, name, obj, type=None)

Construct a new _Label.

def accept_visitor(self, visitor)

def get_children(self, **kwargs)

key = property()

orig_set = property()

back to section top

class LoggingClauseVisitor(ClauseVisitor)

extends ClauseVisitor to include debug logging of all traversal.

To install this visitor, set logging.DEBUG for 'sqlalchemy.sql.ClauseVisitor' before you import the sqlalchemy.sql module.

def traverse(self, obj, stop_on=None)

back to section top