- mysql, postgres: "%" signs in text() constructs are automatically escaped to "%%".

Because of the backwards incompatible nature of this change,
a warning is emitted if '%%' is detected in the string.  [ticket:1267]

3 files changed, 14 insertions, 1 deletions

diff --git a/lib/sqlalchemy/databases/mysql.py b/lib/sqlalchemy/databases/mysql.py
index 86fb7b247..1b977dce9 100644
--- a/lib/sqlalchemy/databases/mysql.py
+++ b/lib/sqlalchemy/databases/mysql.py
@@ -1952,6 +1952,11 @@ class MySQLCompiler(compiler.DefaultCompiler):
         return 'CAST(%s AS %s)' % (self.process(cast.clause), type_)
 
 
+    def post_process_text(self, text):
+        if '%%' in text:
+            util.warn("The SQLAlchemy MySQLDB dialect now automatically escapes '%' in text() expressions to '%%'.")
+        return text.replace('%', '%%')
+
     def get_select_precolumns(self, select):
         if isinstance(select._distinct, basestring):
             return select._distinct.upper() + " "
diff --git a/lib/sqlalchemy/databases/postgres.py b/lib/sqlalchemy/databases/postgres.py
index 273f5859e..6fd0662de 100644
--- a/lib/sqlalchemy/databases/postgres.py
+++ b/lib/sqlalchemy/databases/postgres.py
@@ -719,6 +719,11 @@ class PGCompiler(compiler.DefaultCompiler):
         else:
             return "nextval('%s')" % self.preparer.format_sequence(seq)
 
+    def post_process_text(self, text):
+        if '%%' in text:
+            util.warn("The SQLAlchemy psycopg2 dialect now automatically escapes '%' in text() expressions to '%%'.")
+        return text.replace('%', '%%')
+
     def limit_clause(self, select):
         text = ""
         if select._limit is not None:
diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py
index 0430f053b..b286398bf 100644
--- a/lib/sqlalchemy/sql/compiler.py
+++ b/lib/sqlalchemy/sql/compiler.py
@@ -294,6 +294,9 @@ class DefaultCompiler(engine.Compiled):
     def visit_typeclause(self, typeclause, **kwargs):
         return typeclause.type.dialect_impl(self.dialect).get_col_spec()
 
+    def post_process_text(self, text):
+        return text
+        
     def visit_textclause(self, textclause, **kwargs):
         if textclause.typemap is not None:
             for colname, type_ in textclause.typemap.iteritems():
@@ -308,7 +311,7 @@ class DefaultCompiler(engine.Compiled):
 
         # un-escape any \:params
         return BIND_PARAMS_ESC.sub(lambda m: m.group(1),
-            BIND_PARAMS.sub(do_bindparam, textclause.text)
+            BIND_PARAMS.sub(do_bindparam, self.post_process_text(textclause.text))
         )
 
     def visit_null(self, null, **kwargs):