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| author | Mike Bayer <mike_mp@zzzcomputing.com> | 2021-04-01 17:20:31 -0400 |
|---|---|---|
| committer | Mike Bayer <mike_mp@zzzcomputing.com> | 2021-04-01 18:59:41 -0400 |
| commit | 20c0f774e5517514da811bc446812baa6b1f32f1 (patch) | |
| tree | 31130474fc5aabcd7143ac5b0ba585c25700169a /lib/sqlalchemy/dialects/sqlite | |
| parent | dc5ade010da55c1158ee7294c9e882cc52cd6e01 (diff) | |
| download | sqlalchemy-20c0f774e5517514da811bc446812baa6b1f32f1.tar.gz | |
Default caching to opt-out for 3rd party dialects
Added a new flag to the :class:`_engine.Dialect` class called
:attr:`_engine.Dialect.supports_statement_cache`. This flag now needs to be present
directly on a dialect class in order for SQLAlchemy's
:ref:`query cache <sql_caching>` to take effect for that dialect. The
rationale is based on discovered issues such as :ticket:`6173` revealing
that dialects which hardcode literal values from the compiled statement,
often the numerical parameters used for LIMIT / OFFSET, will not be
compatible with caching until these dialects are revised to use the
parameters present in the statement only. For third party dialects where
this flag is not applied, the SQL logging will show the message "dialect
does not support caching", indicating the dialect should seek to apply this
flag once they have verified that no per-statement literal values are being
rendered within the compilation phase.
Fixes: #6184
Change-Id: I6fd5b5d94200458d4cb0e14f2f556dbc25e27e22
Diffstat (limited to 'lib/sqlalchemy/dialects/sqlite')
| -rw-r--r-- | lib/sqlalchemy/dialects/sqlite/aiosqlite.py | 1 | ||||
| -rw-r--r-- | lib/sqlalchemy/dialects/sqlite/base.py | 1 | ||||
| -rw-r--r-- | lib/sqlalchemy/dialects/sqlite/pysqlcipher.py | 1 | ||||
| -rw-r--r-- | lib/sqlalchemy/dialects/sqlite/pysqlite.py | 1 |
4 files changed, 4 insertions, 0 deletions
diff --git a/lib/sqlalchemy/dialects/sqlite/aiosqlite.py b/lib/sqlalchemy/dialects/sqlite/aiosqlite.py index e4b7d1d52..1d09a619d 100644 --- a/lib/sqlalchemy/dialects/sqlite/aiosqlite.py +++ b/lib/sqlalchemy/dialects/sqlite/aiosqlite.py @@ -299,6 +299,7 @@ class SQLiteExecutionContext_aiosqlite(SQLiteExecutionContext): class SQLiteDialect_aiosqlite(SQLiteDialect_pysqlite): driver = "aiosqlite" + supports_statement_cache = True is_async = True diff --git a/lib/sqlalchemy/dialects/sqlite/base.py b/lib/sqlalchemy/dialects/sqlite/base.py index 691ca642d..83c2a8ea7 100644 --- a/lib/sqlalchemy/dialects/sqlite/base.py +++ b/lib/sqlalchemy/dialects/sqlite/base.py @@ -1796,6 +1796,7 @@ class SQLiteDialect(default.DefaultDialect): supports_cast = True supports_multivalues_insert = True tuple_in_values = True + supports_statement_cache = True default_paramstyle = "qmark" execution_ctx_cls = SQLiteExecutionContext diff --git a/lib/sqlalchemy/dialects/sqlite/pysqlcipher.py b/lib/sqlalchemy/dialects/sqlite/pysqlcipher.py index 8f0f46acb..ff02d4dee 100644 --- a/lib/sqlalchemy/dialects/sqlite/pysqlcipher.py +++ b/lib/sqlalchemy/dialects/sqlite/pysqlcipher.py @@ -98,6 +98,7 @@ from ... import util class SQLiteDialect_pysqlcipher(SQLiteDialect_pysqlite): driver = "pysqlcipher" + supports_statement_cache = True pragmas = ("kdf_iter", "cipher", "cipher_page_size", "cipher_use_hmac") diff --git a/lib/sqlalchemy/dialects/sqlite/pysqlite.py b/lib/sqlalchemy/dialects/sqlite/pysqlite.py index c940faf38..0b091e73b 100644 --- a/lib/sqlalchemy/dialects/sqlite/pysqlite.py +++ b/lib/sqlalchemy/dialects/sqlite/pysqlite.py @@ -443,6 +443,7 @@ class _SQLite_pysqliteDate(DATE): class SQLiteDialect_pysqlite(SQLiteDialect): default_paramstyle = "qmark" + supports_statement_cache = True colspecs = util.update_copy( SQLiteDialect.colspecs, |