feat: support function fetchmany() and fetchall() in python SDK and UT

python/openmldb/dbapi/dbapi.py

@@ -343,14 +343,9 @@ def get_databases(self):
         return self.connection._sdk.getDatabases()
 
     def fetchone(self):
-
-        if self._resultSet is None: return "call fetchone"
+        if self._resultSet is None: raise DatabaseError("query data failed")
         ok = self._resultSet.Next()
         if not ok:
-            self.rowcount = -1
-            self._resultSet = None
-            self.__schema = None
-            self.__getMap = None
             return None
         values = []
         for i in range(self.__schema.GetColumnCnt()):
@@ -362,7 +357,24 @@ def fetchone(self):
 
     @connected
     def fetchmany(self, size=None):
-        raise NotSupportedError("Unsupported in OpenMLDB")
+        if self._resultSet is None: raise DatabaseError("query data failed")
+        if size is None:
+            size = self.arraysize
+        elif size < 0:
+            raise Exception(f"Given size should greater than zero")
+        values = []
+        for k in range(size):
+            ok = self._resultSet.Next()
+            if not ok:
+                break
+            row = []
+            for i in range(self.__schema.GetColumnCnt()):
+                if self._resultSet.IsNULL(i):
+                    row.append(None)
+                else:
+                    row.append(self.__getMap[self.__schema.GetColumnType(i)](i))
+            values.append(tuple(row))
+        return values
 
     def nextset(self):
         raise NotSupportedError("Unsupported in OpenMLDB")
@@ -375,8 +387,8 @@ def setoutputsize(self, size, columns=()):
 
     @connected
     def fetchall(self):
-        raise NotSupportedError("Unsupported in OpenMLDB")
-
+        return self.fetchmany(size=self.rowcount)
+    
     @staticmethod
     def substitute_in_query(string_query, parameters):
         query = string_query

python/openmldb/test/openmldb_client_test.py

@@ -59,7 +59,6 @@ def test_basic(self):
     connection.execute(insert5, ({"col2":"2020-12-29"}));
 
     self.check_fetchmany(connection)
-    self.check_fetchall(connection)
     self.check_exectute_many(connection,insert4)
 
     data = {1000 : [1000, '2020-12-25', 'guangdon', '广州', 1],
@@ -88,6 +87,7 @@ def test_basic(self):
         (1003, '2020-12-28', 'jiangxi', 'nanchang', 4),
         (1004, '2020-12-29', 'hubei', 'wuhan', 5),
     ]
+    self.check_fetchall(connection, expectRows)
     self.check_result(rs, expectRows, 0);
     # test condition select
     rs = connection.execute("select * from tsql1010 where col3 = 'hefei';");
@@ -207,21 +207,16 @@ def check_exectute_many(self,connection,sql):
       pass
 
   def check_fetchmany(self,connection):
-    try:
-      result = connection.execute("select * from tsql1010;")
-      print(result.fetchmany(size=2))
-      self.assertTrue(False)
-    except Exception as e:
-      pass
+    result = connection.execute("select * from tsql1010;")
+    self.assertTrue(result.fetchmany() == [(1002, '2020-12-27', 'fujian', 'fuzhou', 3)])
+    self.assertTrue(result.fetchmany(size=2) == [(1001, '2020-12-26', 'hefei', 'anhui', 2),(1000, '2020-12-25', 'guangdon', '广州', 1)])
+    self.assertTrue(result.fetchmany(size=4) == [(1004, '2020-12-29', 'hubei', 'wuhan', 5),(1003, '2020-12-28', 'jiangxi', 'nanchang', 4)])
 
-  def check_fetchall(self,connection):
-    try:
-      result = connection.execute("select * from tsql1010;")
-      print(result.fetchall())
-      self.assertTrue(False)
-    except Exception as e:
-      pass
-
+  def check_fetchall(self,connection, expect_row):
+    result = connection.execute("select * from tsql1010;")
+    result = sorted(result.fetchall(), key=lambda x: x[0])
+    self.assertTrue(result == expect_row)
+
   def test_parameterized_query(self):
     logging.info("test_parameterized_query...")
     engine = db.create_engine('openmldb:///db_test?zk=127.0.0.1:6181&zkPath=/onebox')