diff options
Diffstat (limited to 'lib/sqlalchemy/sql/expression.py')
| -rw-r--r-- | lib/sqlalchemy/sql/expression.py | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py index 5df3b8794..ed561bbeb 100644 --- a/lib/sqlalchemy/sql/expression.py +++ b/lib/sqlalchemy/sql/expression.py @@ -3924,16 +3924,21 @@ class Select(_SelectBaseMixin, FromClause): return self._get_display_froms() @_generative - def with_hint(self, selectable, text, dialect_name=None): + def with_hint(self, selectable, text, dialect_name='*'): """Add an indexing hint for the given selectable to this :class:`Select`. - The text of the hint is written specific to a specific backend, and - typically uses Python string substitution syntax to render the name - of the table or alias, such as for Oracle:: + The text of the hint is rendered in the appropriate + location for the database backend in use, relative + to the given :class:`.Table` or :class:`.Alias` passed as the + *selectable* argument. The dialect implementation + typically uses Python string substitution syntax + with the token ``%(name)s`` to render the name of + the table or alias. E.g. when using Oracle, the + following:: - select([mytable]).with_hint(mytable, "+ index(%(name)s - ix_mytable)") + select([mytable]).\\ + with_hint(mytable, "+ index(%(name)s ix_mytable)") Would render SQL as:: @@ -3943,13 +3948,11 @@ class Select(_SelectBaseMixin, FromClause): hint to a particular backend. Such as, to add hints for both Oracle and Sybase simultaneously:: - select([mytable]).\ - with_hint(mytable, "+ index(%(name)s ix_mytable)", 'oracle').\ + select([mytable]).\\ + with_hint(mytable, "+ index(%(name)s ix_mytable)", 'oracle').\\ with_hint(mytable, "WITH INDEX ix_mytable", 'sybase') """ - if not dialect_name: - dialect_name = '*' self._hints = self._hints.union({(selectable, dialect_name):text}) @property |