if the left side is a join, it will attempt to join the right
side to the rightmost side of the left first, and not raise
any exceptions about ambiguous join conditions if successful
even if there are further join targets across the rest of
the left. [ticket:1714]
- generalized the "freetds" / "unicode statements" behavior of MS-SQL/pyodbc
into the base Pyodbc connector, as this seems to apply to Sybase as well.
- generalized the python-sybase "use autocommit for DDL" into the pyodbc
connector. With pyodbc, the "autocommit" flag on connection is used,
as Pyodbc seems to have more database conversation than python-sybase that
can't otherwise be suppressed.
- Some platforms will now interpret certain literal values
as non-bind parameters, rendered literally into the SQL
statement. This to support strict SQL-92 rules that are
enforced by some platforms including MS-SQL and Sybase.
In this model, bind parameters aren't allowed in the
columns clause of a SELECT, nor are certain ambiguous
expressions like "?=?". When this mode is enabled, the base
compiler will render the binds as inline literals, but only across
strings and numeric values. Other types such as dates
will raise an error, unless the dialect subclass defines
a literal rendering function for those. The bind parameter
must have an embedded literal value already or an error
is raised (i.e. won't work with straight bindparam('x')).
Dialects can also expand upon the areas where binds are not
accepted, such as within argument lists of functions
(which don't work on MS-SQL when native SQL binding is used).
changes to Enum/SchemaType to re-support adaptation of string types.
This approach can be adapted by "conditional" unicode returning dialects
(i.e. pyodbc and possibly mxodbc) to remove the overhead
of isinstance(value, unicode) calls when the dialect returned type is
of dbapi.UNICODE, dbapi.NVARCHAR, etc.
info from the cursor before commit() is called on the
DBAPI connection in an "autocommit" scenario. This helps
mxodbc with rowcount and is probably a good idea overall.
- cx_oracle wants list(), not tuple(), for empty execute.
- cleaned up plain SQL param handling
upon close() - fixed that.
- Transaction object doesn't rollback or commit if it isn't
"active", allows more accurate nesting of begin/rollback/commit.
- Added basic support for mxODBC [ticket:1710].
- Python unicode objects as binds result in the Unicode type,
not string, thus eliminating a certain class of unicode errors
on drivers that don't support unicode binds.
Mike Bayer