diff --git a/pkg/proxy/backend/authenticator_test.go b/pkg/proxy/backend/authenticator_test.go
index 774c8493..bb354af0 100644
--- a/pkg/proxy/backend/authenticator_test.go
+++ b/pkg/proxy/backend/authenticator_test.go
@@ -27,50 +27,50 @@ func TestUnsupportedCapability(t *testing.T) {
 	cfgs := [][]cfgOverrider{
 		{
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability & ^pnet.ClientSSL
+				cfg.clientConfig.capability &= ^pnet.ClientSSL
 			},
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability | pnet.ClientSSL
+				cfg.clientConfig.capability |= pnet.ClientSSL
 			},
 		},
 		{
 			func(cfg *testConfig) {
-				cfg.backendConfig.capability = defaultTestBackendCapability & ^pnet.ClientSSL
+				cfg.backendConfig.capability &= ^pnet.ClientSSL
 			},
 			func(cfg *testConfig) {
-				cfg.backendConfig.capability = defaultTestBackendCapability | pnet.ClientSSL
+				cfg.backendConfig.capability |= pnet.ClientSSL
 			},
 		},
 		{
 			func(cfg *testConfig) {
-				cfg.backendConfig.capability = defaultTestBackendCapability & ^pnet.ClientDeprecateEOF
+				cfg.backendConfig.capability &= ^pnet.ClientDeprecateEOF
 			},
 			func(cfg *testConfig) {
-				cfg.backendConfig.capability = defaultTestBackendCapability | pnet.ClientDeprecateEOF
+				cfg.backendConfig.capability |= pnet.ClientDeprecateEOF
 			},
 		},
 		{
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability & ^pnet.ClientProtocol41
+				cfg.clientConfig.capability &= ^pnet.ClientProtocol41
 			},
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability | pnet.ClientProtocol41
+				cfg.clientConfig.capability |= pnet.ClientProtocol41
 			},
 		},
 		{
 			func(cfg *testConfig) {
-				cfg.backendConfig.capability = defaultTestClientCapability & ^pnet.ClientPSMultiResults
+				cfg.backendConfig.capability &= ^pnet.ClientPSMultiResults
 			},
 			func(cfg *testConfig) {
-				cfg.backendConfig.capability = defaultTestClientCapability | pnet.ClientPSMultiResults
+				cfg.backendConfig.capability |= pnet.ClientPSMultiResults
 			},
 		},
 		{
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability & ^pnet.ClientPSMultiResults
+				cfg.clientConfig.capability &= ^pnet.ClientPSMultiResults
 			},
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability | pnet.ClientPSMultiResults
+				cfg.clientConfig.capability |= pnet.ClientPSMultiResults
 			},
 		},
 	}
@@ -151,27 +151,27 @@ func TestCapability(t *testing.T) {
 	cfgs := [][]cfgOverrider{
 		{
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability & ^pnet.ClientConnectWithDB
+				cfg.clientConfig.capability &= ^pnet.ClientConnectWithDB
 			},
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability | pnet.ClientConnectWithDB
+				cfg.clientConfig.capability |= pnet.ClientConnectWithDB
 			},
 		},
 		{
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability & ^pnet.ClientConnectAttrs
+				cfg.clientConfig.capability &= ^pnet.ClientConnectAttrs
 			},
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability | pnet.ClientConnectAttrs
+				cfg.clientConfig.capability |= pnet.ClientConnectAttrs
 				cfg.clientConfig.attrs = map[string]string{"key": "value"}
 			},
 		},
 		{
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability & ^pnet.ClientSecureConnection
+				cfg.clientConfig.capability &= ^pnet.ClientSecureConnection
 			},
 			func(cfg *testConfig) {
-				cfg.clientConfig.capability = defaultTestClientCapability | pnet.ClientSecureConnection
+				cfg.clientConfig.capability |= pnet.ClientSecureConnection
 			},
 		},
 	}
diff --git a/pkg/proxy/backend/testsuite_test.go b/pkg/proxy/backend/testsuite_test.go
index c55528a9..477ad15a 100644
--- a/pkg/proxy/backend/testsuite_test.go
+++ b/pkg/proxy/backend/testsuite_test.go
@@ -77,7 +77,10 @@ func getCfgCombinations(cfgs [][]cfgOverrider) [][]cfgOverrider {
 		// Append the cfg to each of the existing overrider list.
 		for _, cfg := range cfgList {
 			for _, o := range cfgOverriders {
-				newOverriders = append(newOverriders, append(o, cfg))
+				newOverrider := make([]cfgOverrider, 0, len(o)+1)
+				newOverrider = append(newOverrider, o...)
+				newOverrider = append(newOverrider, cfg)
+				newOverriders = append(newOverriders, newOverrider)
 			}
 		}
 		cfgOverriders = newOverriders
@@ -187,9 +190,13 @@ func (ts *testSuite) authenticateFirstTime(t *testing.T, c checker) {
 		// Check the data received by client equals to the data sent from the server and vice versa.
 		require.Equal(t, ts.mb.authSucceed, ts.mc.authSucceed)
 		require.Equal(t, ts.mc.username, ts.mb.username)
-		require.Equal(t, ts.mc.dbName, ts.mb.db)
+		if ts.mc.capability&pnet.ClientConnectWithDB > 0 {
+			require.Equal(t, ts.mc.dbName, ts.mb.db)
+		}
 		require.Equal(t, ts.mc.authData, ts.mb.authData)
-		require.Equal(t, ts.mc.attrs, ts.mb.attrs)
+		if ts.mc.capability&pnet.ClientConnectAttrs > 0 {
+			require.Equal(t, ts.mc.attrs, ts.mb.attrs)
+		}
 	}
 }