just in my own testing, if I say insert().return_defaults()
and stringify, I should see it, so make sure all the dialects
default to "insert_returning" etc. , with downgrade on
server version check.
Change-Id: Id64e78fcb03c48b5dcb0feb21cb9cc495edd15e9
Adjusted the fix made for 🎫`8056` which adjusted the escaping of
bound parameter names with special characters such that the escaped names
were translated after the SQL compilation step, which broke a published
recipe on the FAQ illustrating how to merge parameter names into the string
output of a compiled SQL string. The change restores the escaped names that
come from ``compiled.params`` and adds a conditional parameter to
:meth:`.SQLCompiler.construct_params` named ``escape_names`` that defaults
to ``True``, restoring the old behavior by default.
Fixes: #8113
Change-Id: I9cbedb1080bc06d51f287fd2cbf26aaab1c74653
this allows cast() of a label() to propagate the
proxy key outwards in the same way that it apparently
works at the SQL level.
This is stuffing even more rules into naming so basically
seeing how far we can go without other cases starting
to fail.
Fixes: #8084
Change-Id: I20bd97dae798fee6492334c06934e807d0f269ef
in 296c84313a for #5653 we generalized Oracle's
parameter escaping feature into the compiler, so that it could also
work for PostgreSQL. The compiler used quoted names within parameter
dictionaries, which then led to the complexity that all functions
which interpreted keys from the compiled_params dict had to
also quote the param names to use the dictionary. This
extra complexity was not added to the ORM peristence.py however,
which led to the versioning id feature being broken as well as
other areas where persistence.py relies on naming schemes present
in context.compiled_params. It also was not added to the
"processors" lookup which led to #8053, that added this escaping
to that part of the compiler.
To both solve the whole problem as well as simplify the compiler
quite a bit, move the actual application of the escaped names
to be as late as possible, when default.py builds the final list
of parameters. This is more similar to how it worked previously
where OracleExecutionContext would be late-applying these
escaped names. This re-establishes context.compiled_params as
deterministically named regardless of dialect in use and moves
out the complexity of the quoted param names to be only at the
cursor.execute stage.
Fixed bug, likely a regression from 1.3, where usage of column names that
require bound parameter escaping, more concretely when using Oracle with
column names that require quoting such as those that start with an
underscore, or in less common cases with some PostgreSQL drivers when using
column names that contain percent signs, would cause the ORM versioning
feature to not work correctly if the versioning column itself had such a
name, as the ORM assumes certain bound parameter naming conventions that
were being interfered with via the quotes. This issue is related to
🎫`8053` and essentially revises the approach towards fixing this,
revising the original issue 🎫`5653` that created the initial
implementation for generalized bound-parameter name quoting.
Fixes: #8056
Change-Id: I57b064e8f0d070e328b65789c30076f6a0ca0fef
Fixed SQL compiler issue where the "bind processing" function for a bound
parameter would not be correctly applied to a bound value if the bound
parameter's name were "escaped". Concretely, this applies, among other
cases, to Oracle when a :class:`.Column` has a name that itself requires
quoting, such that the quoting-required name is then used for the bound
parameters generated within DML statements, and the datatype in use
requires bind processing, such as the :class:`.Enum` datatype.
Fixes: #8053
Change-Id: I39d060a87e240b4ebcfccaa9c535e971b7255d99
The FROM clauses that are established on a :func:`_sql.select` construct
when using the :meth:`_sql.Select.select_from` method will now render first
in the FROM clause of the rendered SELECT, which serves to maintain the
ordering of clauses as was passed to the :meth:`_sql.Select.select_from`
method itself without being affected by the presence of those clauses also
being mentioned in other parts of the query. If other elements of the
:class:`_sql.Select` also generate FROM clauses, such as the columns clause
or WHERE clause, these will render after the clauses delivered by
:meth:`_sql.Select.select_from` assuming they were not explictly passed to
:meth:`_sql.Select.select_from` also. This improvement is useful in those
cases where a particular database generates a desirable query plan based on
a particular ordering of FROM clauses and allows full control over the
ordering of FROM clauses.
Fixes: #7888
Change-Id: I740f262a3841f829239011120a59b5e58452db5b
An informative error is raised if two individual :class:`.BindParameter`
objects share the same name, yet one is used within an "expanding" context
(typically an IN expression) and the other is not; mixing the same name in
these two different styles of usage is not supported and typically the
``expanding=True`` parameter should be set on the parameters that are to
receive list values outside of IN expressions (where ``expanding`` is set
by default).
Fixes: #8018
Change-Id: Ie707f29680eea16b9e421af93560ac1958e11a54
Fixed regression caused by 🎫`7823` which impacted the caching
system, such that bound parameters that had been "cloned" within ORM
operations, such as polymorphic loading, would in some cases not acquire
their correct execution-time value leading to incorrect bind values being
rendered.
Fixes: #7903
Change-Id: I61c802749b859bebeb127d24e66d6e77d13ce57a
the pep484 task becomes more intense as there is mounting
pressure to come up with a consistency in how data moves
from end-user to instance variable.
current thinking is coming into:
1. there are _typing._XYZArgument objects that represent "what the
user sent"
2. there's the roles, which represent a kind of "filter" for different
kinds of objects. These are mostly important as the argument
we pass to coerce().
3. there's the thing that coerce() returns, which should be what the
construct uses as its internal representation of the thing.
This is _typing._XYZElement.
but there's some controversy over whether or
not we should pass actual ClauseElements around by their role
or not. I think we shouldn't at the moment, but this makes the
"role-ness" of something a little less portable. Like, we have
to set DMLTableRole for TableClause, Join, and Alias, but then
also we have to repeat those three types in order to set up
_DMLTableElement.
Other change introduced here, there was a deannotate=True
for the left/right of a sql.join(). All tests pass without that.
I'd rather not have that there as if we have a join(A, B) where
A, B are mapped classes, we want them inside of the _annotations.
The rationale seems to be performance, but this performance can
be illustrated to be on the compile side which we hope is cached
in the normal case.
CTEs now accommodate for text selects including recursive.
Get typing to accommodate "util.preloaded" cleanly; add "preloaded"
as a real module. This seemed like we would have needed
pep562 `__getattr__()` but we don't, just set names in
globals() as we import them.
References: #6810
Change-Id: I34d17f617de2fe2c086fc556bd55748dc782faf0
the truediv test suite didn't have __backend__ so wasn't running
for every DB except in the main build. Repaired this as well
as truediv support to preserve the right-hand side type
when casting to numeric, if the right type is already a
numeric type.
also fixed a memusage test that relies on savepoints so was
not running under gerrit runs.
Change-Id: I3be223fdf697af9c1ed61b70d621f57cbbb7a92b
Added an additional lookup step to the compiler which will track all FROM
clauses which are tables, that may have the same name shared in multiple
schemas where one of the schemas is the implicit "default" schema; in this
case, the table name when referring to that name without a schema
qualification will be rendered with an anonymous alias name at the compiler
level in order to disambiguate the two (or more) names. The approach of
schema-qualifying the normally unqualified name with the server-detected
"default schema name" value was also considered, however this approach
doesn't apply to Oracle nor is it accepted by SQL Server, nor would it work
with multiple entries in the PostgreSQL search path. The name collision
issue resolved here has been identified as affecting at least Oracle,
PostgreSQL, SQL Server, MySQL and MariaDB.
Fixes: #7471
Change-Id: Id65e7ca8c43fe8d95777084e8d5ec140ebcd784d
Fixed issue where :meth:`_sql.Select.correlate_except` method, when passed
either the ``None`` value or no arguments, would not correlate any elements
when used in an ORM context (that is, passing ORM entities as FROM
clauses), rather than causing all FROM elements to be considered as
"correlated" in the same way which occurs when using Core-only constructs.
Fixes: #7514
Change-Id: Ic4a5252c8f3c1140aba6c308264948f3a91f33f5
Implemented full support for "truediv" and "floordiv" using the
"/" and "//" operators. A "truediv" operation between two expressions
using :class:`_types.Integer` now considers the result to be
:class:`_types.Numeric`, and the dialect-level compilation will cast
the right operand to a numeric type on a dialect-specific basis to ensure
truediv is achieved. For floordiv, conversion is also added for those
databases that don't already do floordiv by default (MySQL, Oracle) and
the ``FLOOR()`` function is rendered in this case, as well as for
cases where the right operand is not an integer (needed for PostgreSQL,
others).
The change resolves issues both with inconsistent behavior of the
division operator on different backends and also fixes an issue where
integer division on Oracle would fail to be able to fetch a result due
to inappropriate outputtypehandlers.
Fixes: #4926
Change-Id: Id54cc018c1fb7a49dd3ce1216d68d40f43fe2659
Support multiple clause elements in the :meth:`_sql.Exists.where` method,
unifying the api with the on presented by a normal :func:`_sql.select`
construct.
Fixes: #7386
Change-Id: I5df20478008cd5167053d357cbfad8a641c62b44
the _CompileLabel class included ``__slots__`` but these
weren't used as the superclasses included slots.
Create a ``__slots__`` superclass for ``ClauseElement``,
creating a new class of compilable SQL elements that don't
include heavier features like caching, annotations and
cloning, which are meant to be used only in an ad-hoc
compiler fashion. Create new ``CompilerColumnElement``
from that which serves in column-oriented contexts, but
similarly does not include any expression operator support
as it is intended to be used only to generate a string.
Apply this to both
``_CompileLabel`` as well as PostgreSQL ``_ColonCast``,
which does not actually subclass ``ColumnElement`` as this
class has memoized attributes that aren't worth changing,
and does not include SQL operator capabilities as these
are not needed for these compiler-only objects.
this allows us to more inexpensively add new ad-hoc
labels / casts etc. at compile time, as we will be seeking
to expand out the typecasts that are needed for PostgreSQL
dialects in a subsequent patch.
Change-Id: I52973ae3295cb6e2eb0d7adc816c678a626643ed
Adjusted the compiler's generation of "post compile" symbols including
those used for "expanding IN" as well as for the "schema translate map" to
not be based directly on plain bracketed strings with underscores, as this
conflicts directly with SQL Server's quoting format of also using brackets,
which produces false matches when the compiler replaces "post compile" and
"schema translate" symbols. The issue created easy to reproduce examples
both with the :meth:`.Inspector.get_schema_names` method when used in
conjunction with the
:paramref:`_engine.Connection.execution_options.schema_translate_map`
feature, as well in the unlikely case that a symbol overlapping with the
internal name "POSTCOMPILE" would be used with a feature like "expanding
in".
Fixes: #7300
Change-Id: I6255c850b140522a4aba95085216d0bca18ce230
The major action here is to lift and move future.Connection
and future.Engine fully into sqlalchemy.engine.base. This
removes lots of engine concepts, including:
* autocommit
* Connection running without a transaction, autobegin
is now present in all cases
* most "autorollback" is obsolete
* Core-level subtransactions (i.e. MarkerTransaction)
* "branched" connections, copies of connections
* execution_options() returns self, not a new connection
* old argument formats, distill_params(), simplifies calling
scheme between engine methods
* before/after_execute() events (oriented towards compiled constructs)
don't emit for exec_driver_sql(). before/after_cursor_execute()
is still included for this
* old helper methods superseded by context managers, connection.transaction(),
engine.transaction() engine.run_callable()
* ancient engine-level reflection methods has_table(), table_names()
* sqlalchemy.testing.engines.proxying_engine
References: #7257
Change-Id: Ib20ed816642d873b84221378a9ec34480e01e82c
Adjusted the "column disambiguation" logic that's new in 1.4, where the
same expression repeated gets an "extra anonymous" label, so that the logic
more aggressively deduplicates those labels when the repeated element
is the same Python expression object each time, as occurs in cases like
when using "singleton" values like :func:`_sql.null`. This is based on
the observation that at least some databases (e.g. MySQL, but not SQLite)
will raise an error if the same label is repeated inside of a subquery.
Related to 🎫`7153`, fixed an issue where result column lookups
would fail for "adapted" SELECT statements that selected for
"constant" value expressions most typically the NULL expression,
as would occur in such places as joined eager loading in conjunction
with limit/offset. This was overall a regression due to issue
🎫`6259` which removed all "adaption" for constants like NULL,
"true", and "false", but this broke the case where the same adaption
logic were used to match the constant to a labeled expression referring
to the constant in a subquery.
Fixes: #7153Fixes: #7154
Change-Id: I43823343721b9e70524ea3f5e8f39dd543a3e92b
this appears to be unnecessary and prevents end-user
literal_binds case from working.
Fixed issue where the ``literal_binds`` compiler flag, as used externally
to render bound parameters inline, would fail to work when used with a
certain class of parameters known as "literal_execute", which covers things
like LIMIT and OFFSET values for dialects where the drivers don't allow a
bound parameter, such as SQL Server's "TOP" clause. The issue locally
seemed to affect only the MSSQL dialect.
Fixes: #6863
Change-Id: Ia74cff5b0107b129a11b9b965883552b2962e449
Fixed issue where a bound parameter object that was "cloned" would cause a
name conflict in the compiler, if more than one clone of this parameter
were used at the same time in a single statement. This could occur in
particular with things like ORM single table inheritance queries that
indicated the same "discriminator" value multiple times in one query.
Fixes: #6824
Change-Id: Iba7a786fc5a2341ff7d07fc666d24ed790ad4fe8
Fixed issue in CTE constructs where a recursive CTE that referred to a
SELECT that has duplicate column names, which are typically deduplicated
using labeling logic in 1.4, would fail to refer to the deduplicated label
name correctly within the WITH clause.
As part of this change we are also attempting to remove the
behavior of SelectStatementGrouping forcing off the "asfrom"
contextual flag, which will have the result of additional labeling
being applied to some UNION and similar statements when they are
interpreted as subqueries. To maintain compatibility with
"grouping", the Grouping/SelectStatementGrouping are now broken
out into two separate compiler cases, as the "asfrom" logic appears
to be tailored towards table valued SELECTS as column expressions.
Fixes: #6710
Change-Id: I8af07a5c670dbe5736cd9f16084ef82f5e4c8642
To service #6718 and #6710, the system by which columns are
given labels in a SELECT statement as well as the system that
gives them keys in a .c or .selected_columns collection have
been refactored to provide a single source of truth for
both, in constrast to the previous approach that included
similar logic repeated in slightly different ways.
Main ideas:
1. ColumnElement attributes ._label, ._anon_label, ._key_label
are renamed to include the letters "tq", meaning
"table-qualified" - these labels are only used when rendering
a SELECT that has LABEL_STYLE_TABLENAME_PLUS_COL for its
label style; as this label style is primarily legacy, the
"tq" names should be isolated so that in a 2.0 style application
these aren't being used at all
2. The means by which the "labels" and "proxy keys" for the elements
of a SELECT has been centralized to a single source of truth;
previously, the three of _generate_columns_plus_names,
_generate_fromclause_column_proxies, and _column_naming_convention
all had duplicated rules between them, as well as that there
were a little bit of labeling rules in compiler._label_select_column
as well; by this we mean that the various "anon_label" "anon_key"
methods on ColumnElement were called by all four of these methods,
where there were many cases where it was necessary that one method
comes up with the same answer as another of the methods. This
has all been centralized into _generate_columns_plus_names
for all the names except the "proxy key", which is generated
by _column_naming_convention.
3. compiler._label_select_column has been rewritten to both not make
any naming decisions nor any "proxy key" decisions, only whether
to label or not to label; the _generate_columns_plus_names method
gives it the information, where the proxy keys come from
_column_naming_convention; previously, these proxy keys were matched
based on restatement of similar (but not really the same) logic in
two places. The heuristics of "whether to label or not to label"
are also reorganized to be much easier to read and understand.
4. a new method compiler._label_returning_column is added for dialects
to use in their "generate returning columns" methods. A
github search reveals a small number of third party dialects also
doing this using the prior _label_select_column method so we
try to make sure _label_select_column continues to work the
exact same way for that specific use case; for the "SELECT" use
case it now needs
5. After some attempts to do it different ways, for the case where
_proxy_key is giving us some kind of anon label, we are hard
changing it to "_no_label" right now, as there's not currently
a way to fully match anonymized labels from stmt.c or
stmt.selected_columns to what will be in the result map. The
idea of "_no_label" is to encourage the user to use label('name')
for columns they want to be able to target by string name that
don't have a natural name.
Change-Id: I7a92a66f3a7e459ccf32587ac0a3c306650daf11
Fixed critical regression where bound parameter tracking as used in the SQL
caching system could fail to track all parameters for the case where the
same SQL expression containing a parameter were used in an ORM-related
query using a feature such as class inheritance, which was then embedded in
an enclosing expression which would make use of that same expression
multiple times, such as a UNION. The ORM would individually copy the
individual SELECT statements as part of compilation with class inheritance,
which then embedded in the enclosing statement would fail to accommodate
for all parameters. The logic that tracks this condition has been adjusted
to work for multiple copies of a parameter.
Fixes: #6391
Change-Id: I6db5dee0d361a3bb58d753a2d27ef2eee2b369c5
Repaired and solidified issues regarding custom functions and other
arbitrary expression constructs which within SQLAlchemy's column labeling
mechanics would seek to use ``str(obj)`` to get a string representation to
use as an anonymous column name in the ``.c`` collection of a subquery.
This is a very legacy behavior that performs poorly and leads to lots of
issues, so has been revised to no longer perform any compilation by
establishing specific methods on :class:`.FunctionElement` to handle this
case, as SQL functions are the only use case that it came into play. An
effect of this behavior is that an unlabeled column expression with no
derivable name will be given an arbitrary label starting with the prefix
``"_no_label"`` in the ``.c`` collection of a subquery; these were
previously being represented either as the generic stringification of that
expression, or as an internal symbol.
This change seeks to make the concept of "anon name" more private
and renames anon_label and anon_key_label to _anon_name_label
and _anon_key_label. There's no end-user utility to these accessors
and we need to be able to reorganize these as well.
Fixes: #6256
Change-Id: Ie63c86b20ca45873affea78500388da94cf8bf94
Fixed the "stringify" compiler to support a basic stringification
of a "multirow" INSERT statement, i.e. one with multiple tuples
following the VALUES keyword.
Change-Id: I1fe38d204d9965275d3a72157d5a72a53bec4b11
Fixed regression where usage of a token in the
:paramref:`_engine.Connection.execution_options.schema_translate_map`
dictionary which contained special characters such as braces would fail to
be substituted properly. Use of square bracket characters ``[]`` is now
explicitly disallowed as these are used as a delimiter character in the
current implementation.
Fixes: #6216
Change-Id: I7ccfc2292b17340054cedf485ed1adf3119b96c8
Executing a :class:`_sql.Subquery` using :meth:`_engine.Connection.execute`
is deprecated and will emit a deprecation warning; this use case was an
oversight that should have been removed from 1.4. The operation will now
execute the underlying :class:`_sql.Select` object directly for backwards
compatibility. Similarly, the :class:`_sql.CTE` class is also not
appropriate for execution. In 1.3, attempting to execute a CTE would result
in an invalid "blank" SQL statement being executed; since this use case was
not working it now raises :class:`_exc.ObjectNotExecutableError`.
Previously, 1.4 was attempting to execute the CTE as a statement however it
was working only erratically.
The change also breaks out StatementRole from ReturnsRowsRole, as these
roles should not be in the same lineage (some statements don't return
rows, the whole class of ReturnsRows that are from clauses are
not statements). Consolidate StatementRole and
CoerceTextStatementRole as there's no usage difference between
these. Simplify some old tests that were trying to make
sure that "execution options" didn't transmit from a cte/subquery
out to a select; as cte/subuqery() aren't executable in any case
the options are removed.
Fixes: #6204
Change-Id: I62613b7ab418afdd22c409eae75659e3f52fb65f
Fixed further issues in the same area as that of 🎫`6173` released in
1.4.5, where a "postcompile" parameter, again most typically those used for
LIMIT/OFFSET rendering in Oracle and SQL Server, would fail to be processed
correctly if the same parameter rendered in multiple places in the
statement.
Fixes: #6202
Change-Id: I95c355aa52a7546fe579ad67f9a8402a213cb79d
Fixed regression where usage of the standalone :func:`_sql.distinct()` used
in the form of being directly SELECTed would fail to be locatable in the
result set by column identity, which is how the ORM locates columns. While
standalone :func:`_sql.distinct()` is not oriented towards being directly
SELECTed (use :meth:`_sql.select.distinct` for a regular
``SELECT DISTINCT..``) , it was usable to a limited extent in this way
previously (but wouldn't work in subqueries, for example). The column
targeting for unary expressions such as "DISTINCT <col>" has been improved
so that this case works again, and an additional improvement has been made
so that usage of this form in a subquery at least generates valid SQL which
was not the case previously.
The change additionally enhances the ability to target elements in
``row._mapping`` based on SQL expression objects in ORM-enabled
SELECT statements, including whether the statement was invoked by
``connection.execute()`` or ``session.execute()``.
Fixes: #6008
Change-Id: I5cfa39435f5418861d70a7db8f52ab4ced6a792e
Altered the compilation for the :class:`.CTE` construct so that a string is
returned representing the inner SELECT statement if the :class:`.CTE` is
stringified directly, outside of the context of an enclosing SELECT; This
is the same behavior of :meth:`_FromClause.alias` and
:meth:`_SelectStatement.subquery`. Previously, a blank string would be
returned as the CTE is normally placed above a SELECT after that SELECT has
been generated, which is generally misleading when debugging.
Change-Id: Id3007c28e4a7a56d867e850bb890752946bd8f6f
References: #5988
Fixed regression where the "unsupported compilation error" for unknown
datatypes would fail to raise correctly.
Fixes: #5979
Change-Id: I984fe95666813832ab5bdfc568322e2aa7cc3db0
Forked from I22f6cf0f0b3360e55299cdcb2452cead2b2458ea
we are attempting to decide the case for columns mapped
under a different name. since the .key feature of
Column seems to support this fully, see if an annotation
can be used to indicate an effective .key for a column.
The effective change is that the labeling of column expressions
in rows has been improved to retain the original name of the ORM
attribute even if used in a subquery.
References: #5933
Change-Id: If251f556f7d723f50d349f765f1690d6c679d2ef
Adjusted the "literal_binds" feature of :class:`_sql.Compiler` to render
NULL for a bound parameter that has ``None`` as the value, either
explicitly passed or omitted. The previous error message "bind parameter
without a renderable value" is removed, and a missing or ``None`` value
will now render NULL in all cases. Previously, rendering of NULL was
starting to happen for DML statements due to internal refactorings, but was
not explicitly part of test coverage, which it now is.
While no error is raised, when the context is within that of a column
comparison, and the operator is not "IS"/"IS NOT", a warning is emitted
that this is not generally useful from a SQL perspective.
Fixes: #5888
Change-Id: Id5939d8dbfb1156a9f8a7f7e76cf18327155331a
Replace :meth:`_orm.Query.with_labels` and
:meth:`_sql.GenerativeSelect.apply_labels` with explicit getters and
setters ``get_label_style`` and ``set_label_style`` to accommodate the
three supported label styles: ``LABEL_STYLE_DISAMBIGUATE_ONLY`` (default),
``LABEL_STYLE_TABLENAME_PLUS_COL``, and ``LABEL_STYLE_NONE``.
In addition, for Core and "future style" ORM queries,
``LABEL_STYLE_DISAMBIGUATE_ONLY`` is now the default label style. This
style differs from the existing "no labels" style in that labeling is
applied in the case of column name conflicts; with ``LABEL_STYLE_NONE``, a
duplicate column name is not accessible via name in any case.
For legacy ORM queries using :class:`_query.Query`, the table-plus-column
names labeling style applied by ``LABEL_STYLE_TABLENAME_PLUS_COL``
continues to be used so that existing test suites and logging facilities
see no change in behavior by default, however this style of labeling is no
longer required for SQLAlchemy queries to function, as result sets are
commonly matched to columns using a positional approach since SQLAlchemy
1.0.
Within test suites, all use of apply_labels() / use_labels
now uses the new methods. New tests added to
test/sql/test_deprecations.py nad test/orm/test_deprecations.py
to cover just the old apply_labels() method call. Tests
in ORM that made explicit use apply_labels()/ etc. where it isn't needed
for the ORM to work correctly use default label style now.
Co-authored-by: Mike Bayer <mike_mp@zzzcomputing.com>
Fixes: #4757
Change-Id: I5fdcd2ed4ae8c7fe62f8be2b6d0e8f66409b6a54
To allow the "connection" pytest fixture and others work
correctly in conjunction with setup/teardown that expects
to be external to the transaction, remove and prevent any usage
of "xdist" style names that are hardcoded by pytest to run
inside of fixtures, even function level ones. Instead use
pytest autouse fixtures to implement our own
r"setup|teardown_test(?:_class)?" methods so that we can ensure
function-scoped fixtures are run within them. A new more
explicit flow is set up within plugin_base and pytestplugin
such that the order of setup/teardown steps, which there are now
many, is fully documented and controllable. New granularity
has been added to the test teardown phase to distinguish
between "end of the test" when lock-holding structures on
connections should be released to allow for table drops,
vs. "end of the test plus its teardown steps" when we can
perform final cleanup on connections and run assertions
that everything is closed out.
From there we can remove most of the defensive "tear down everything"
logic inside of engines which for many years would frequently dispose
of pools over and over again, creating for a broken and expensive
connection flow. A quick test shows that running test/sql/ against
a single Postgresql engine with the new approach uses 75% fewer new
connections, creating 42 new connections total, vs. 164 new
connections total with the previous system.
As part of this, the new fixtures metadata/connection/future_connection
have been integrated such that they can be combined together
effectively. The fixture_session(), provide_metadata() fixtures
have been improved, including that fixture_session() now strongly
references sessions which are explicitly torn down before
table drops occur afer a test.
Major changes have been made to the
ConnectionKiller such that it now features different "scopes" for
testing engines and will limit its cleanup to those testing
engines corresponding to end of test, end of test class, or
end of test session. The system by which it tracks DBAPI
connections has been reworked, is ultimately somewhat similar to
how it worked before but is organized more clearly along
with the proxy-tracking logic. A "testing_engine" fixture
is also added that works as a pytest fixture rather than a
standalone function. The connection cleanup logic should
now be very robust, as we now can use the same global
connection pools for the whole suite without ever disposing
them, while also running a query for PostgreSQL
locks remaining after every test and assert there are no open
transactions leaking between tests at all. Additional steps
are added that also accommodate for asyncio connections not
explicitly closed, as is the case for legacy sync-style
tests as well as the async tests themselves.
As always, hundreds of tests are further refined to use the
new fixtures where problems with loose connections were identified,
largely as a result of the new PostgreSQL assertions,
many more tests have moved from legacy patterns into the newest.
An unfortunate discovery during the creation of this system is that
autouse fixtures (as well as if they are set up by
@pytest.mark.usefixtures) are not usable at our current scale with pytest
4.6.11 running under Python 2. It's unclear if this is due
to the older version of pytest or how it implements itself for
Python 2, as well as if the issue is CPU slowness or just large
memory use, but collecting the full span of tests takes over
a minute for a single process when any autouse fixtures are in
place and on CI the jobs just time out after ten minutes.
So at the moment this patch also reinvents a small version of
"autouse" fixtures when py2k is running, which skips generating
the real fixture and instead uses two global pytest fixtures
(which don't seem to impact performance) to invoke the
"autouse" fixtures ourselves outside of pytest.
This will limit our ability to do more with fixtures
until we can remove py2k support.
py.test is still observed to be much slower in collection in the
4.6.11 version compared to modern 6.2 versions, so add support for new
TOX_POSTGRESQL_PY2K and TOX_MYSQL_PY2K environment variables that
will run the suite for fewer backends under Python 2. For Python 3
pin pytest to modern 6.2 versions where performance for collection
has been improved greatly.
Includes the following improvements:
Fixed bug in asyncio connection pool where ``asyncio.TimeoutError`` would
be raised rather than :class:`.exc.TimeoutError`. Also repaired the
:paramref:`_sa.create_engine.pool_timeout` parameter set to zero when using
the async engine, which previously would ignore the timeout and block
rather than timing out immediately as is the behavior with regular
:class:`.QueuePool`.
For asyncio the connection pool will now also not interact
at all with an asyncio connection whose ConnectionFairy is
being garbage collected; a warning that the connection was
not properly closed is emitted and the connection is discarded.
Within the test suite the ConnectionKiller is now maintaining
strong references to all DBAPI connections and ensuring they
are released when tests end, including those whose ConnectionFairy
proxies are GCed.
Identified cx_Oracle.stmtcachesize as a major factor in Oracle
test scalability issues, this can be reset on a per-test basis
rather than setting it to zero across the board. the addition
of this flag has resolved the long-standing oracle "two task"
error problem.
For SQL Server, changed the temp table style used by the
"suite" tests to be the double-pound-sign, i.e. global,
variety, which is much easier to test generically. There
are already reflection tests that are more finely tuned
to both styles of temp table within the mssql test
suite. Additionally, added an extra step to the
"dropfirst" mechanism for SQL Server that will remove
all foreign key constraints first as some issues were
observed when using this flag when multiple schemas
had not been torn down.
Identified and fixed two subtle failure modes in the
engine, when commit/rollback fails in a begin()
context manager, the connection is explicitly closed,
and when "initialize()" fails on the first new connection
of a dialect, the transactional state on that connection
is still rolled back.
Fixes: #5826Fixes: #5827
Change-Id: Ib1d05cb8c7cf84f9a4bfd23df397dc23c9329bfe
Added parameters :paramref:`_ddl.CreateTable.if_not_exists`,
:paramref:`_ddl.CreateIndex.if_not_exists`,
:paramref:`_ddl.DropTable.if_exists` and
:paramref:`_ddl.DropIndex.if_exists` to the :class:`_ddl.CreateTable`,
:class:`_ddl.DropTable`, :class:`_ddl.CreateIndex` and
:class:`_ddl.DropIndex` constructs which result in "IF NOT EXISTS" / "IF
EXISTS" DDL being added to the CREATE/DROP. These phrases are not accepted
by all databases and the operation will fail on a database that does not
support it as there is no similarly compatible fallback within the scope of
a single DDL statement. Pull request courtesy Ramon Williams.
Fixes: #2843Closes: #5663
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5663
Pull-request-sha: 748b847234
Change-Id: I6a2b1f697993ed49c31584f0a31887fb0a868ed3
Dialect-specific constructs such as
:meth:`_postgresql.Insert.on_conflict_do_update` can now stringify in-place
without the need to specify an explicit dialect object. The constructs,
when called upon for ``str()``, ``print()``, etc. now have internal
direction to call upon their appropriate dialect rather than the
"default"dialect which doesn't know how to stringify these. The approach
is also adapted to generic schema-level create/drop such as
:class:`_schema.AddConstraint`, which will adapt its stringify dialect to
one indicated by the element within it, such as the
:class:`_postgresql.ExcludeConstraint` object.
mostly towards being able to provide doctest-style
examples for "on conflict" constructs using print statements.
Change-Id: I4b855516fe6dee2df77744c1bb21a373d7fbab93
Add SelectBase.exists() method as it seems strange this is
not available already. The Exists construct itself does
not provide full SELECT-building capabilities so it makes
sense this should be used more like a scalar_subquery.
Make sure stream_results is getting set up when yield_per
is used, for 2.0 style statements as well. this was
hardcoded inside of Query.yield_per() and is now moved
to take place within QueryContext.
Change-Id: Icafcd4fd9b708772343d56edf40995c9e8f835d6
The operator changes are:
* `isfalse` is now `is_false`
* `isnot_distinct_from` is now `is_not_distinct_from`
* `istrue` is now `is_true`
* `notbetween` is now `not_between`
* `notcontains` is now `not_contains`
* `notendswith` is now `not_endswith`
* `notilike` is now `not_ilike`
* `notlike` is now `not_like`
* `notmatch` is now `not_match`
* `notstartswith` is now `not_startswith`
* `nullsfirst` is now `nulls_first`
* `nullslast` is now `nulls_last`
Because these are core operators, the internal migration strategy for this
change is to support legacy terms for an extended period of time -- if not
indefinitely -- but update all documentation, tutorials, and internal usage
to the new terms. The new terms are used to define the functions, and
the legacy terms have been deprecated into aliases of the new terms.
Fixes: #5435
Change-Id: Ifbd7cb1cdda5981990243c4fc4b4ff467dc132ac
Fixed structural compiler issue where some constructs such as MySQL /
PostgreSQL "on conflict / on duplicate key" would rely upon the state of
the :class:`_sql.Compiler` object being fixed against their statement as
the top level statement, which would fail in cases where those statements
are branched from a different context, such as a DDL construct linked to a
SQL statement.
Fixes: #5656
Change-Id: I568bf40adc7edcf72ea6c7fd6eb9d07790de189e
Improved support for column names that contain percent signs in the string,
including repaired issues involving anoymous labels that also embedded a
column name with a percent sign in it, as well as re-established support
for bound parameter names with percent signs embedded on the psycopg2
dialect, using a late-escaping process similar to that used by the
cx_Oracle dialect.
* Added new constructor for _anonymous_label() that ensures incoming
string tokens based on column or table names will have percent
signs escaped; abstracts away the format of the label.
* generalized cx_Oracle's quoted_bind_names facility into the compiler
itself, and leveraged this for the psycopg2 dialect's issue with
percent signs in names as well. the parameter substitution is now
integrated with compiler.construct_parameters() as well as the
recently reworked set_input_sizes(), reducing verbosity in the
cx_Oracle dialect.
Fixes: #5653
Change-Id: Ia2ad13ea68b4b0558d410026e5a33f5cb3fbab2c
Add support to ``FETCH {FIRST | NEXT} [ count ] {ROW | ROWS}
{ONLY | WITH TIES}`` in the select for the supported backends,
currently PostgreSQL, Oracle and MSSQL.
Fixes: #5576
Change-Id: Ibb5871a457c0555f82b37e354e7787d15575f1f7
It's better, the majority of these changes look more readable to me.
also found some docstrings that had formatting / quoting issues.
Change-Id: I582a45fde3a5648b2f36bab96bad56881321899b
This change includes mainly that the bracketed use within
select() is moved to positional, and keyword arguments are
removed from calls to the select() function. it does not
yet fully address other issues such as keyword arguments passed
to the table.select().
Additionally, allows False / None to both be considered
as "disable" for all of select.correlate(), select.correlate_except(),
query.correlate(), which establishes consistency with
passing of ``False`` for the legact select(correlate=False)
argument.
Change-Id: Ie6c6e6abfbd3d75d4c8de504c0cf0159e6999108
Mike Bayer