diff --git a/src/main/java/com/alibaba/druid/wall/spi/WallVisitorUtils.java b/src/main/java/com/alibaba/druid/wall/spi/WallVisitorUtils.java
index 6c93a2e95f..9c6182419e 100644
--- a/src/main/java/com/alibaba/druid/wall/spi/WallVisitorUtils.java
+++ b/src/main/java/com/alibaba/druid/wall/spi/WallVisitorUtils.java
@@ -189,7 +189,7 @@ public class WallVisitorUtils {
         SQLExpr expr = x.getExpr();
 
         if (expr instanceof SQLVariantRefExpr) {
-            if ("@".equals(((SQLVariantRefExpr) expr).getName())) {
+            if (!isTopSelectStatement(expr) && "@".equals(((SQLVariantRefExpr) expr).getName())) {
                 addViolation(visitor, ErrorCode.EVIL_NAME, "@ not allow", x);
             }
         }
@@ -1057,7 +1057,7 @@ public class WallVisitorUtils {
                     leftIsName = true;
                 }
             }
-            
+
             if ((!leftIsName) && caseExpr.getItems().size() > 0) {
                 SQLCaseExpr.Item item = caseExpr.getItems().get(0);
                 Object conditionVal = getValue(visitor, item.getConditionExpr());
@@ -1072,7 +1072,7 @@ public class WallVisitorUtils {
 
         return null;
     }
-    
+
     public static Object eval(String dbType, SQLObject sqlObject, List<Object> parameters) {
         SQLEvalVisitor visitor = SQLEvalVisitorUtils.createEvalVisitor(dbType);
         visitor.setParameters(parameters);
@@ -1455,6 +1455,38 @@ public class WallVisitorUtils {
         return false;
     }
 
+    private static boolean isTopSelectStatement(SQLObject x) {
+
+        for (;;) {
+            if ((x.getParent() instanceof SQLExpr) || (x.getParent() instanceof Item)) {
+                x = x.getParent();
+            } else {
+                break;
+            }
+        }
+
+        if (!(x.getParent() instanceof SQLSelectItem)) {
+            return false;
+        }
+        SQLSelectItem item = (SQLSelectItem) x.getParent();
+        if (!(item.getParent() instanceof SQLSelectQueryBlock)) {
+            return false;
+        }
+
+        SQLSelectQueryBlock queryBlock = (SQLSelectQueryBlock) item.getParent();
+        if (!(queryBlock.getParent() instanceof SQLSelect)) {
+            return false;
+        }
+
+        SQLSelect select = (SQLSelect) queryBlock.getParent();
+        if (!(select.getParent() instanceof SQLSelectStatement)) {
+            return false;
+        }
+
+        SQLSelectStatement stmt = (SQLSelectStatement) select.getParent();
+        return stmt.getParent() == null;
+    }
+
     public static boolean check(WallVisitor visitor, SQLExprTableSource x) {
         final WallTopStatementContext topStatementContext = wallTopStatementContextLocal.get();
 
diff --git a/src/test/java/com/alibaba/druid/bvt/filter/wall/MySqlWallTest91.java b/src/test/java/com/alibaba/druid/bvt/filter/wall/MySqlWallTest91.java
index 939af92cc7..f6816afb9b 100644
--- a/src/test/java/com/alibaba/druid/bvt/filter/wall/MySqlWallTest91.java
+++ b/src/test/java/com/alibaba/druid/bvt/filter/wall/MySqlWallTest91.java
@@ -43,6 +43,7 @@ public class MySqlWallTest91 extends TestCase {
         provider.getConfig().setSchemaCheck(true);
         provider.getConfig().setLimitZeroAllow(true);
         provider.getConfig().setCommentAllow(true);
+        provider.getConfig().setConditionDoubleConstAllow(true);
 
         return provider;
     }
@@ -151,6 +152,14 @@ public class MySqlWallTest91 extends TestCase {
         }
     }
 
+    public void test_true4() {
+        WallProvider provider = initWallProvider();
+        {
+            String sql = "SELECT 10006,@";
+            Assert.assertTrue(provider.checkValid(sql));
+        }
+    }
+
     public void test_true() throws Exception {
         WallProvider provider = initWallProvider();
         {
diff --git a/src/test/java/com/alibaba/druid/bvt/filter/wall/SQLServerWallTest_0.java b/src/test/java/com/alibaba/druid/bvt/filter/wall/SQLServerWallTest_0.java
index 71456fc4e2..ba6a2707a3 100644
--- a/src/test/java/com/alibaba/druid/bvt/filter/wall/SQLServerWallTest_0.java
+++ b/src/test/java/com/alibaba/druid/bvt/filter/wall/SQLServerWallTest_0.java
@@ -43,6 +43,7 @@ public class SQLServerWallTest_0 extends TestCase {
         provider.getConfig().setSchemaCheck(true);
         provider.getConfig().setLimitZeroAllow(true);
         provider.getConfig().setCommentAllow(true);
+        provider.getConfig().setConditionDoubleConstAllow(true);
 
         return provider;
     }
@@ -119,10 +120,10 @@ public class SQLServerWallTest_0 extends TestCase {
         WallProvider provider = initWallProvider();
         {
             String sql = "SELECT tableid, chnname "//
-                    + "FROM r_temptable "//
-                    + "INNER JOIN  sys_func_pwr ss ON r_temptable.tableid = ss.mainid "//
-                    + "INNER JOIN  sys_func_pwr sys ON ss.parentid = sys.funcid  " //
-                    + "WHERE (ismaintable = 1)  and  1=1  and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 550) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 551) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 391) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 552) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 393) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 396) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 4628) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 4836) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 394) AND (functype = 8) AND (Closed = 0))) and ss.funcid <> 4298 and ss.funcid <> 7441 AND (ss.funcid IN  (SELECT DISTINCT funcid FROM sys_func_pwr  WHERE (functype = 8) AND (Closed = 0)  ))  ORDER BY sys.sortflag ,ss.sortflag ";
+                         + "FROM r_temptable "//
+                         + "INNER JOIN  sys_func_pwr ss ON r_temptable.tableid = ss.mainid "//
+                         + "INNER JOIN  sys_func_pwr sys ON ss.parentid = sys.funcid  " //
+                         + "WHERE (ismaintable = 1)  and  1=1  and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 550) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 551) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 391) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 552) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 393) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 396) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 4628) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 4836) AND (functype = 8) AND (Closed = 0))) and (r_temptable.tableid NOT IN (SELECT DISTINCT mainid FROM sys_func_pwr WHERE (parentid = 394) AND (functype = 8) AND (Closed = 0))) and ss.funcid <> 4298 and ss.funcid <> 7441 AND (ss.funcid IN  (SELECT DISTINCT funcid FROM sys_func_pwr  WHERE (functype = 8) AND (Closed = 0)  ))  ORDER BY sys.sortflag ,ss.sortflag ";
             Assert.assertTrue(provider.checkValid(sql));
         }
     }