diff options
Diffstat (limited to 'lib/sqlalchemy/sql/expression.py')
| -rw-r--r-- | lib/sqlalchemy/sql/expression.py | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py index 9324ed6a0..4b49dc0bc 100644 --- a/lib/sqlalchemy/sql/expression.py +++ b/lib/sqlalchemy/sql/expression.py @@ -437,7 +437,8 @@ def case(whens, value=None, else_=None): The expressions used for THEN and ELSE, when specified as strings, will be interpreted as bound values. To specify textual SQL expressions - for these, use the text(<string>) construct. + for these, use the literal_column(<string>) or + text(<string>) construct. The expressions used for the WHEN criterion may only be literal strings when "value" is @@ -457,6 +458,15 @@ def case(whens, value=None, else_=None): 'manager': emp.c.salary * 3, }) + Using ``literal_column()``, to allow for databases that + do not support bind parameters in the `then` clause. The type + can be specified which determines the type of the `case()` construct + overall:: + + case([(orderline.c.qty > 100, literal_column("'greaterthan100'", String)), + (orderline.c.qty > 10, literal_column("'greaterthan10'", String)) + ], else_=literal_column("'lethan10'", String)) + """ return _Case(whens, value=value, else_=else_) |