support offset (#1172)

* support offset fix #847,#739,#647. * update limit ut Co-authored-by: 小圈圈 <rtttte@qq.com>
hhyo · Sep 16, 2021 · f370593 · f370593
1 parent ae54ae6
commit f370593
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Showing 2 changed files with 16 additions and 8 deletions.
diff --git a/sql/engines/mysql.py b/sql/engines/mysql.py
@@ -198,17 +198,25 @@ def filter_sql(self, sql='', limit_num=0):
         sql = sql.rstrip(';').strip()
         if re.match(r"^select", sql, re.I):
             # LIMIT N
-            limit_n = re.compile(r'limit([\s]*\d+[\s]*)$', re.I)
-            # LIMIT N, N 或LIMIT N OFFSET N
-            limit_offset = re.compile(r'limit([\s]*\d+[\s]*)(,|offset)([\s]*\d+[\s]*)$', re.I)
+            limit_n = re.compile(r'limit\s+(\d+)\s*$', re.I)
+            # LIMIT M OFFSET N
+            limit_offset = re.compile(r'limit\s+(\d+)\s+offset\s+(\d+)\s*$', re.I)
+            # LIMIT M,N
+            offset_comma_limit = re.compile(r'limit\s+(\d+)\s*,\s*(\d+)\s*$', re.I)
             if limit_n.search(sql):
                 sql_limit = limit_n.search(sql).group(1)
                 limit_num = min(int(limit_num), int(sql_limit))
                 sql = limit_n.sub(f'limit {limit_num};', sql)
             elif limit_offset.search(sql):
-                sql_limit = limit_offset.search(sql).group(3)
+                sql_limit = limit_offset.search(sql).group(1)
+                sql_offset = limit_offset.search(sql).group(2)
                 limit_num = min(int(limit_num), int(sql_limit))
-                sql = limit_offset.sub(f'limit {limit_num};', sql)
+                sql = limit_offset.sub(f'limit {limit_num} offset {sql_offset};', sql)
+            elif offset_comma_limit.search(sql):
+                sql_offset = offset_comma_limit.search(sql).group(1)
+                sql_limit = offset_comma_limit.search(sql).group(2)
+                limit_num = min(int(limit_num), int(sql_limit))
+                sql = offset_comma_limit.sub(f'limit {sql_offset},{limit_num};', sql)
             else:
                 sql = f'{sql} limit {limit_num};'
         else:

diff --git a/sql/engines/tests.py b/sql/engines/tests.py
@@ -355,19 +355,19 @@ def test_filter_sql_with_limit_offset(self):
         new_engine = MysqlEngine(instance=self.ins1)
         sql_without_limit = 'select user from usertable limit 10 offset 100'
         check_result = new_engine.filter_sql(sql=sql_without_limit, limit_num=1)
-        self.assertEqual(check_result, 'select user from usertable limit 1;')
+        self.assertEqual(check_result, 'select user from usertable limit 1 offset 100;')
 
     def test_filter_sql_with_limit_nn(self):
         new_engine = MysqlEngine(instance=self.ins1)
         sql_without_limit = 'select user from usertable limit 10, 100'
         check_result = new_engine.filter_sql(sql=sql_without_limit, limit_num=1)
-        self.assertEqual(check_result, 'select user from usertable limit 1;')
+        self.assertEqual(check_result, 'select user from usertable limit 10,1;')
 
     def test_filter_sql_upper(self):
         new_engine = MysqlEngine(instance=self.ins1)
         sql_without_limit = 'SELECT USER FROM usertable LIMIT 10, 100'
         check_result = new_engine.filter_sql(sql=sql_without_limit, limit_num=1)
-        self.assertEqual(check_result, 'SELECT USER FROM usertable limit 1;')
+        self.assertEqual(check_result, 'SELECT USER FROM usertable limit 10,1;')
 
     def test_filter_sql_not_select(self):
         new_engine = MysqlEngine(instance=self.ins1)