- Fixed SQLite reflection methods so that non-presentrel_0_4

      cursor.description, which triggers an auto-cursor
      close, will be detected so that no results doesn't
      fail on recent versions of pysqlite which raise
      an error when fetchone() called with no rows present.

2 files changed, 17 insertions, 5 deletions

diff --git a/CHANGES b/CHANGES
index 8a1beede3..7873ac1b5 100644
--- a/CHANGES
+++ b/CHANGES
@@ -44,6 +44,13 @@ CHANGES
       creates an arbitrarily large number of engines
       or dialects.   There is a small performance penalty
       which will be resolved in 0.6.  [ticket:1299]
+
+-sqlite
+    - Fixed SQLite reflection methods so that non-present
+      cursor.description, which triggers an auto-cursor
+      close, will be detected so that no results doesn't
+      fail on recent versions of pysqlite which raise 
+      an error when fetchone() called with no rows present.
       
 - postgres
     - Added Index reflection support to Postgres, using a
diff --git a/lib/sqlalchemy/databases/sqlite.py b/lib/sqlalchemy/databases/sqlite.py
index 04f59a839..d7d6d7a1f 100644
--- a/lib/sqlalchemy/databases/sqlite.py
+++ b/lib/sqlalchemy/databases/sqlite.py
@@ -333,7 +333,8 @@ class SQLiteDialect(default.DefaultDialect):
         else:
             pragma = "PRAGMA "
         qtable = quote(table_name)
-        cursor = connection.execute("%stable_info(%s)" % (pragma, qtable))
+        cursor = _pragma_cursor(connection.execute("%stable_info(%s)" % (pragma, qtable)))
+            
         row = cursor.fetchone()
 
         # consume remaining rows, to work around
@@ -351,7 +352,7 @@ class SQLiteDialect(default.DefaultDialect):
             pragma = "PRAGMA %s." % preparer.quote_identifier(table.schema)
         qtable = preparer.format_table(table, False)
 
-        c = connection.execute("%stable_info(%s)" % (pragma, qtable))
+        c = _pragma_cursor(connection.execute("%stable_info(%s)" % (pragma, qtable)))
         found_table = False
         while True:
             row = c.fetchone()
@@ -390,7 +391,7 @@ class SQLiteDialect(default.DefaultDialect):
         if not found_table:
             raise exceptions.NoSuchTableError(table.name)
 
-        c = connection.execute("%sforeign_key_list(%s)" % (pragma, qtable))
+        c = _pragma_cursor(connection.execute("%sforeign_key_list(%s)" % (pragma, qtable)))
         fks = {}
         while True:
             row = c.fetchone()
@@ -418,7 +419,7 @@ class SQLiteDialect(default.DefaultDialect):
         for name, value in fks.iteritems():
             table.append_constraint(schema.ForeignKeyConstraint(value[0], value[1]))
         # check for UNIQUE indexes
-        c = connection.execute("%sindex_list(%s)" % (pragma, qtable))
+        c = _pragma_cursor(connection.execute("%sindex_list(%s)" % (pragma, qtable)))
         unique_indexes = []
         while True:
             row = c.fetchone()
@@ -436,7 +437,11 @@ class SQLiteDialect(default.DefaultDialect):
                     break
                 cols.append(row[2])
 
-
+def _pragma_cursor(cursor):
+    if cursor.closed or not cursor.cursor.description:
+        cursor._fetchone_impl = lambda: None
+    return cursor
+        
 class SQLiteCompiler(compiler.DefaultCompiler):
     functions = compiler.DefaultCompiler.functions.copy()
     functions.update (