and not its contained expression, if the dialect reports true for supports_simple_order_by_label.
the flag is not propagated forwards, meant to closely mimic the syntax Postgres expects which is
that only a simple name can be in the ORDER BY, not a more complex expression or function call
with the label name embedded (mysql and sqlite support more complex expressions).
This further sets the standard for propigation of **kwargs within compiler, that we can't just send
**kwargs along blindly to each XXX.process() call; whenever a **kwarg needs to propagate through,
most methods will have to be aware of it and know when they should send it on forward and when not.
This was actually already the case with result_map as well.
The supports_simple_order_by dialect flag defaults to True but is conservatively explicitly set to
False on all dialects except SQLite/MySQL/Postgres to start.
[ticket:1068]
- sql
- func.count() with no arguments renders as COUNT(*),
equivalent to func.count(text('*')).
+
+ - simple label names in ORDER BY expressions render as
+ themselves, and not as a re-statement of their
+ corresponding expression. This feature is currently
+ enabled only for SQLite, MySQL, and Postgres.
+ It can be enabled on other dialects as each is shown
+ to support this behavior. [ticket:1068]
- ext
- Class-bound attributes sent as arguments to
name = 'access'
supports_sane_rowcount = False
supports_sane_multi_rowcount = False
+ supports_simple_order_by_label = False
def type_descriptor(self, typeobj):
newobj = types.adapt_type(typeobj, self.colspecs)
max_identifier_length = 31
preexecute_pk_sequences = True
supports_pk_autoincrement = False
+ supports_simple_order_by_label = False
def __init__(self, type_conv=200, concurrency_level=1, **kwargs):
default.DefaultDialect.__init__(self, **kwargs)
yield co
else:
yield c
- columns = [self.process(c, render_labels=True)
+ columns = [self.process(c, within_columns_clause=True)
for c in flatten_columnlist(returning_cols)]
text += ' RETURNING ' + ', '.join(columns)
return text
default_paramstyle = 'qmark'
# for informix 7.31
max_identifier_length = 18
+ supports_simple_order_by_label = False
def __init__(self, use_ansi=True, **kwargs):
self.use_ansi = use_ansi
else:
return compiler.DefaultCompiler.visit_function( self , func )
- def visit_clauselist(self, list):
+ def visit_clauselist(self, list, within_order_by=False, **kwargs):
try:
li = [ c for c in list.clauses if c.name != 'oid' ]
except:
li = [ c for c in list.clauses ]
- return ', '.join([s for s in [self.process(c) for c in li] if s is not None])
+ return ', '.join([s for s in [self.process(c, within_order_by=within_order_by) for c in li] if s is not None])
class InfoSchemaGenerator(compiler.SchemaGenerator):
def get_column_specification(self, column, first_pk=False):
supports_sane_rowcount = True
supports_sane_multi_rowcount = False
preexecute_pk_sequences = True
+ supports_simple_order_by_label = False
# MaxDB-specific
datetimeformat = 'internal'
class MSSQLDialect(default.DefaultDialect):
name = 'mssql'
+ supports_simple_order_by_label = False
+
colspecs = {
sqltypes.Unicode : MSNVarchar,
sqltypes.Integer : MSInteger,
preexecute_pk_sequences = True
supports_pk_autoincrement = False
default_paramstyle = 'named'
+ supports_simple_order_by_label = False
def __init__(self, use_ansi=True, auto_setinputsizes=True, auto_convert_lobs=True, threaded=True, allow_twophase=True, arraysize=50, **kwargs):
default.DefaultDialect.__init__(self, **kwargs)
yield co
else:
yield c
- columns = [self.process(c, render_labels=True) for c in flatten_columnlist(returning_cols)]
+ columns = [self.process(c, within_columns_clause=True) for c in flatten_columnlist(returning_cols)]
text += ' RETURNING ' + string.join(columns, ', ')
return text
supports_unicode_statements = False
supports_sane_rowcount = False
supports_sane_multi_rowcount = False
+ supports_simple_order_by_label = False
def __new__(cls, dbapi=None, *args, **kwargs):
if cls != SybaseSQLDialect:
dbapi_type_map = {}
default_paramstyle = 'named'
supports_default_values = True
+ supports_simple_order_by_label = True
def __init__(self, convert_unicode=False, assert_unicode=False, encoding='utf-8', paramstyle=None, dbapi=None, **kwargs):
self.convert_unicode = convert_unicode
def visit_grouping(self, grouping, **kwargs):
return "(" + self.process(grouping.element) + ")"
- def visit_label(self, label, result_map=None, render_labels=False):
- if not render_labels:
- return self.process(label.element)
-
- labelname = self._truncated_identifier("colident", label.name)
+ def visit_label(self, label, result_map=None, within_columns_clause=False, within_order_by=False):
+ # only render labels within the columns clause
+ # or ORDER BY clause of a select. dialect-specific compilers
+ # can modify this behavior.
+ if within_columns_clause:
+ labelname = self._truncated_identifier("colident", label.name)
- if result_map is not None:
- result_map[labelname.lower()] = (label.name, (label, label.element, labelname), label.element.type)
+ if result_map is not None:
+ result_map[labelname.lower()] = (label.name, (label, label.element, labelname), label.element.type)
- return " ".join([self.process(label.element), self.operator_string(operators.as_), self.preparer.format_label(label, labelname)])
+ return " ".join([self.process(label.element), self.operator_string(operators.as_), self.preparer.format_label(label, labelname)])
+ elif within_order_by and self.dialect.supports_simple_order_by_label:
+ labelname = self._truncated_identifier("colident", label.name)
+ return self.preparer.format_label(label, labelname)
+ else:
+ return self.process(label.element)
+
def visit_column(self, column, result_map=None, **kwargs):
if column._is_oid:
def visit_null(self, null, **kwargs):
return 'NULL'
- def visit_clauselist(self, clauselist, **kwargs):
+ def visit_clauselist(self, clauselist, within_order_by=False, **kwargs):
sep = clauselist.operator
if sep is None:
sep = " "
sep = ', '
else:
sep = " " + self.operator_string(clauselist.operator) + " "
- return sep.join(s for s in (self.process(c) for c in clauselist.clauses)
+ return sep.join(s for s in (self.process(c, within_order_by=within_order_by) for c in clauselist.clauses)
if s is not None)
def visit_calculatedclause(self, clause, **kwargs):
else:
return ".".join(func.packagenames + [name]) % {'expr':self.function_argspec(func)}
- def function_argspec(self, func):
- return self.process(func.clause_expr)
+ def function_argspec(self, func, **kwargs):
+ return self.process(func.clause_expr, **kwargs)
def function_string(self, func):
return self.functions.get(func.__class__, self.functions.get(func.name, func.name + "%(expr)s"))
else:
return text
- def visit_unary(self, unary, **kwargs):
- s = self.process(unary.element)
+ def visit_unary(self, unary, within_order_by=False, **kwargs):
+ s = self.process(unary.element, within_order_by=within_order_by)
if unary.operator:
s = self.operator_string(unary.operator) + " " + s
if unary.modifier:
[c for c in [
self.process(
self.label_select_column(select, co, asfrom=asfrom),
- render_labels=True,
+ within_columns_clause=True,
**column_clause_args)
for co in select.inner_columns
]
return select._distinct and "DISTINCT " or ""
def order_by_clause(self, select):
- order_by = self.process(select._order_by_clause)
+ order_by = self.process(select._order_by_clause, within_order_by=True)
if order_by:
return " ORDER BY " + order_by
else:
assert row['anon_1'] == 8
assert row['anon_2'] == 10
+ def test_order_by_label(self):
+ """test that a label within an ORDER BY works on each backend.
+
+ simple labels in ORDER BYs now render as the actual labelname
+ which not every database supports.
+
+ """
+ users.insert().execute(
+ {'user_id':7, 'user_name':'jack'},
+ {'user_id':8, 'user_name':'ed'},
+ {'user_id':9, 'user_name':'fred'},
+ )
+
+ concat = ("test: " + users.c.user_name).label('thedata')
+ self.assertEquals(
+ select([concat]).order_by(concat).execute().fetchall(),
+ [("test: ed",), ("test: fred",), ("test: jack",)]
+ )
+
+ concat = ("test: " + users.c.user_name).label('thedata')
+ self.assertEquals(
+ select([concat]).order_by(desc(concat)).execute().fetchall(),
+ [("test: jack",), ("test: fred",), ("test: ed",)]
+ )
+
+ concat = ("test: " + users.c.user_name).label('thedata')
+ self.assertEquals(
+ select([concat]).order_by(concat + "x").execute().fetchall(),
+ [("test: ed",), ("test: fred",), ("test: jack",)]
+ )
+
+
def test_row_comparison(self):
users.insert().execute(user_id = 7, user_name = 'jack')
rp = users.select().execute().fetchone()
from sqlalchemy import *
from sqlalchemy import exc, sql, util
from sqlalchemy.sql import table, column, compiler
+from sqlalchemy.engine import default
from sqlalchemy.databases import sqlite, postgres, mysql, oracle, firebird, mssql
from testlib import *
x = func.lala(table1.c.myid).label('foo')
self.assert_compile(select([x], x==5), "SELECT lala(mytable.myid) AS foo FROM mytable WHERE lala(mytable.myid) = :param_1")
+ def test_labels_in_expressions(self):
+ """test that label() constructs in ORDER BY render as the labelname.
+
+ Postgres' behavior was used as the guide for this,
+ so that only a simple label expression
+ and not a more complex expression involving the label
+ name would be rendered using the label name.
+
+ """
+ lab1 = (table1.c.myid + "12").label('foo')
+ lab2 = func.somefunc(table1.c.name).label('bar')
+
+ dialect = default.DefaultDialect()
+ self.assert_compile(select([lab1, lab2]).order_by(lab1, desc(lab2)),
+ "SELECT mytable.myid + :myid_1 AS foo, somefunc(mytable.name) AS bar FROM mytable ORDER BY foo, bar DESC",
+ dialect=dialect
+ )
+
+ # the function embedded label renders as the function
+ self.assert_compile(select([lab1, lab2]).order_by(func.hoho(lab1), desc(lab2)),
+ "SELECT mytable.myid + :myid_1 AS foo, somefunc(mytable.name) AS bar FROM mytable ORDER BY hoho(mytable.myid + :myid_1), bar DESC",
+ dialect=dialect
+ )
+
+ # binary expressions render as the expression without labels
+ self.assert_compile(select([lab1, lab2]).order_by(lab1 + "test"),
+ "SELECT mytable.myid + :myid_1 AS foo, somefunc(mytable.name) AS bar FROM mytable ORDER BY mytable.myid + :myid_1 + :param_1",
+ dialect=dialect
+ )
+
+ # labels within functions in the columns clause render with the expression
+ self.assert_compile(
+ select([lab1, func.foo(lab1)]),
+ "SELECT mytable.myid + :myid_1 AS foo, foo(mytable.myid + :myid_1) AS foo_1 FROM mytable",
+ dialect=dialect
+ )
+
+ dialect = default.DefaultDialect()
+ dialect.supports_simple_order_by_label = False
+ self.assert_compile(select([lab1, lab2]).order_by(lab1, desc(lab2)),
+ "SELECT mytable.myid + :myid_1 AS foo, somefunc(mytable.name) AS bar FROM mytable ORDER BY mytable.myid + :myid_1, somefunc(mytable.name) DESC",
+ dialect=dialect
+ )
+ self.assert_compile(select([lab1, lab2]).order_by(func.hoho(lab1), desc(lab2)),
+ "SELECT mytable.myid + :myid_1 AS foo, somefunc(mytable.name) AS bar FROM mytable ORDER BY hoho(mytable.myid + :myid_1), somefunc(mytable.name) DESC",
+ dialect=dialect
+ )
+
def test_conjunctions(self):
self.assert_compile(
and_(table1.c.myid == 12, table1.c.name=='asdf', table2.c.othername == 'foo', "sysdate() = today()"),
projects / thirdparty / sqlalchemy / sqlalchemy.git / commitdiff
