diff --git a/core/src/main/java/jef/query/QueryBuilder.java b/core/src/main/java/jef/query/QueryBuilder.java
index 88e4654..b62febe 100644
--- a/core/src/main/java/jef/query/QueryBuilder.java
+++ b/core/src/main/java/jef/query/QueryBuilder.java
@@ -47,7 +47,8 @@ public class QueryBuilder extends ExpressionVisitor {
     }
 
     public void visitField(FieldExpression expr) {
-        if (expr.getSchema() != null && !expr.getSchema().isBlank()) {
+        if (expr.getSchema() != null && !expr.getSchema().isBlank()
+            && expr.getTable() != null && !expr.getTable().isBlank()) {
             query += "`" + expr.getSchema() + "`.";
         }
         if (expr.getTable() != null && !expr.getTable().isBlank()) {
@@ -92,7 +93,8 @@ public class QueryBuilder extends ExpressionVisitor {
         for (int i = 0; i < expr.getSorts().size(); i++) {
             query += " ";
             var sort = expr.getSorts().get(i);
-            if (sort.getExpr().getSchema() != null && !sort.getExpr().getSchema().isBlank()) {
+            if (sort.getExpr().getSchema() != null && !sort.getExpr().getSchema().isBlank()
+                && sort.getExpr().getTable() != null && !sort.getExpr().getTable().isBlank()) {
                 query += "`" + sort.getExpr().getSchema() + "`.";
             }
             if (sort.getExpr().getTable() != null && !sort.getExpr().getTable().isBlank()) {
@@ -135,7 +137,7 @@ public class QueryBuilder extends ExpressionVisitor {
         if (wrap) {
             query += ")";
         }
-        if (expr.getFromAlias().length() > 0 && expr.getFromAlias().charAt(0) >= 'a') {
+        if (expr.getFromAlias().length() > 0 && expr.getFromAlias().charAt(0) >= 'a') {//TODO this is bad check
             query += " " + expr.getFromAlias();
         }
     }
diff --git a/core/src/test/java/jef/query/QueryBuilderTest.java b/core/src/test/java/jef/query/QueryBuilderTest.java
index c642490..13e3eaa 100644
--- a/core/src/test/java/jef/query/QueryBuilderTest.java
+++ b/core/src/test/java/jef/query/QueryBuilderTest.java
@@ -1,96 +1,201 @@
 package jef.query;
 
-import jef.DbSet;
+import jef.expressions.AndExpression;
+import jef.expressions.BinaryExpression;
+import jef.expressions.ConstantExpression;
+import jef.expressions.FieldExpression;
+import jef.expressions.IntermediateFieldExpression;
+import jef.expressions.LimitExpression;
+import jef.expressions.NullExpression;
+import jef.expressions.OrExpression;
+import jef.expressions.OrderExpression;
+import jef.expressions.ParameterExpression;
+import jef.expressions.SelectExpression;
+import jef.expressions.TableExpression;
+import jef.expressions.TernaryExpression;
+import jef.expressions.UnaryExpression;
+import jef.expressions.WhereExpression;
 import jef.serializable.SerializableObject;
 import lombok.Getter;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import java.util.Arrays;
 import java.util.List;
 
 class QueryBuilderTest {
     @Test
-    public void testAnd() {
+    void visitAnd() {
         var v = new QueryBuilder();
-        v.visit(new DbSet<>(TestClass.class, "table1")
-                .filter(e -> e.i == 0 && e.i == 1)
-                .getExpression());
-        Assertions.assertEquals("SELECT * FROM (SELECT * FROM `table1`) a WHERE `a`.`i` = 0 AND `a`.`i` = 1", v.getQuery());
+        v.visitAnd(new AndExpression(ConstantExpression.V0, ConstantExpression.V1));
+        Assertions.assertEquals("0 AND 1", v.getQuery());
     }
 
     @Test
-    public void testBinary() {
+    void visitBinary() {
         var v = new QueryBuilder();
-        v.visit(new DbSet<>(TestClass.class, "table1")
-                .filter(e -> e.i == 0)
-                .getExpression());
-        Assertions.assertEquals("SELECT * FROM (SELECT * FROM `table1`) a WHERE `a`.`i` = 0", v.getQuery());
+        v.visitBinary(new BinaryExpression(ConstantExpression.V0, ConstantExpression.V1, BinaryExpression.Operator.EQ));
+        Assertions.assertEquals("0 = 1", v.getQuery());
     }
 
     @Test
-    public void testConstant() {
+    void visitConstant() {
         var v = new QueryBuilder();
-        v.visit(new DbSet<>(TestClass.class, "table1")
-                .filter(e -> true)
-                .getExpression());
-        Assertions.assertEquals("SELECT * FROM (SELECT * FROM `table1`) a WHERE 1", v.getQuery());
+        v.visitConstant(ConstantExpression.V0);
+        Assertions.assertEquals("0", v.getQuery());
     }
 
     @Test
-    public void testLimit() {
+    void visitField() {
         var v = new QueryBuilder();
-        v.visit(new DbSet<>(TestClass.class, "table1")
-                .filter(e -> e.i == 0 && e.i == 1)
-                .skip(3).limit(5)
-                .getExpression());
-        Assertions.assertEquals("SELECT * FROM (SELECT * FROM (SELECT * FROM `table1`) a WHERE `a`.`i` = 0 AND `a`.`i` = 1) b OFFSET 3 LIMIT 5", v.getQuery());
+        v.visitField(new FieldExpression("schema", "table", "name", null));
+        Assertions.assertEquals("`schema`.`table`.`name`", v.getQuery());
+
+        v = new QueryBuilder();
+        v.visitField(new FieldExpression(null, "table", "name", null));
+        Assertions.assertEquals("`table`.`name`", v.getQuery());
+
+        v = new QueryBuilder();
+        v.visitField(new FieldExpression("schema", null, "name", null));
+        Assertions.assertEquals("`name`", v.getQuery());
+
+        v = new QueryBuilder();
+        v.visitField(new FieldExpression(null, null, "name", null));
+        Assertions.assertEquals("`name`", v.getQuery());
     }
 
     @Test
-    public void testNull() {
+    void visitIntermediateField() {
         var v = new QueryBuilder();
-        v.visit(new DbSet<>(TestClass.class, "table1")
-                .filter(e -> e.o == null)
-                .getExpression());
-        Assertions.assertEquals("SELECT * FROM (SELECT * FROM `table1`) a WHERE `a`.`o` IS NULL", v.getQuery());
+        v.visitIntermediateField(new IntermediateFieldExpression("value", null));
+        Assertions.assertEquals("value", v.getQuery());
     }
 
     @Test
-    public void testParameter() {
-        var s = List.of(1, 3);
+    void visitLimit() {
         var v = new QueryBuilder();
-        v.visit(new DbSet<>(TestClass.class, "table1")
-                .filter(e -> s.contains(e.i))
-                .getExpression());
-        Assertions.assertEquals("SELECT * FROM (SELECT * FROM `table1`) a WHERE `a`.`i` IN (1, 3)", v.getQuery());
+        v.visitLimit(new LimitExpression(ConstantExpression.V0, 3L, 5L));
+        Assertions.assertEquals("0 OFFSET 3 LIMIT 5", v.getQuery());
     }
 
     @Test
-    public void testOr() {
+    void visitNull() {
         var v = new QueryBuilder();
-        v.visit(new DbSet<>(TestClass.class, "table1")
-                .filter(e -> e.i == 0 || e.i == 1)
-                .getExpression());
-        Assertions.assertEquals("SELECT * FROM (SELECT * FROM `table1`) a WHERE `a`.`i` = 0 OR `a`.`i` = 1", v.getQuery());
+        v.visitNull(NullExpression.INSTANCE);
+        Assertions.assertEquals("NULL", v.getQuery());
     }
 
     @Test
-    public void testOrder() {
+    void visitOr() {
         var v = new QueryBuilder();
-        v.visit(new DbSet<>(TestClass.class, "table1")
-                .filter(e -> e.i == 0 && e.i == 1)
-                .sorted(e -> e.getI()).thenSortedDescending(e -> e.getD())
-                .getExpression());
-        Assertions.assertEquals("SELECT * FROM (SELECT * FROM (SELECT * FROM `table1`) a WHERE `a`.`i` = 0 AND `a`.`i` = 1) b ORDER BY `b`.`i` ASC, `b`.`d` DESC", v.getQuery());
+        v.visitOr(new OrExpression(ConstantExpression.V0, ConstantExpression.V1));
+        Assertions.assertEquals("0 OR 1", v.getQuery());
     }
 
     @Test
-    public void testUnary() {
+    void visitOrder() {
+        //multiple sorts
         var v = new QueryBuilder();
-        v.visit(new DbSet<>(TestClass.class, "table1")
-                .filter(e -> e.o != null)
-                .getExpression());
-        Assertions.assertEquals("SELECT * FROM (SELECT * FROM `table1`) a WHERE `a`.`o` IS NOT NULL", v.getQuery());
+        v.visitOrder(new OrderExpression(ConstantExpression.V0, List.of(
+                new OrderExpression.Sort(new FieldExpression(null, null, "name1", null), OrderExpression.SortDirection.ASCENDING),
+                new OrderExpression.Sort(new FieldExpression(null, null, "name2", null), OrderExpression.SortDirection.DESCENDING))));
+        Assertions.assertEquals("0 ORDER BY `name1` ASC, `name2` DESC", v.getQuery());
+
+        //with schema and table
+        v = new QueryBuilder();
+        v.visitOrder(new OrderExpression(ConstantExpression.V0, List.of(
+                new OrderExpression.Sort(new FieldExpression("schema", "table", "name", null), OrderExpression.SortDirection.ASCENDING))));
+        Assertions.assertEquals("0 ORDER BY `schema`.`table`.`name` ASC", v.getQuery());
+
+        //with table
+        v = new QueryBuilder();
+        v.visitOrder(new OrderExpression(ConstantExpression.V0, List.of(
+                new OrderExpression.Sort(new FieldExpression(null, "table", "name", null), OrderExpression.SortDirection.ASCENDING))));
+        Assertions.assertEquals("0 ORDER BY `table`.`name` ASC", v.getQuery());
+
+        //with schema
+        v = new QueryBuilder();
+        v.visitOrder(new OrderExpression(ConstantExpression.V0, List.of(
+                new OrderExpression.Sort(new FieldExpression("schema", null, "name", null), OrderExpression.SortDirection.ASCENDING))));
+        Assertions.assertEquals("0 ORDER BY `name` ASC", v.getQuery());
+
+        //without schema and table
+        v = new QueryBuilder();
+        v.visitOrder(new OrderExpression(ConstantExpression.V0, List.of(
+                new OrderExpression.Sort(new FieldExpression(null, null, "name", null), OrderExpression.SortDirection.ASCENDING))));
+        Assertions.assertEquals("0 ORDER BY `name` ASC", v.getQuery());
+    }
+
+    @Test
+    void visitParameter() {
+        //isInput
+        var v = new QueryBuilder();
+        v.visitParameter(new ParameterExpression(0, null, true, null));
+        Assertions.assertEquals("param #0", v.getQuery());
+
+        //value == null
+        v = new QueryBuilder();
+        v.visitParameter(new ParameterExpression(0, null, false, null));
+        Assertions.assertEquals("NULL", v.getQuery());
+
+        //value == null
+        v = new QueryBuilder();
+        v.visitParameter(new ParameterExpression(0, Arrays.asList(null, "value"), false, null));
+        Assertions.assertEquals("(NULL, value)", v.getQuery());
+
+        //value == null
+        var v2 = new QueryBuilder();
+        Assertions.assertThrows(UnsupportedOperationException.class, () -> v2.visitParameter(new ParameterExpression(0, "value", false, null)));
+    }
+
+    @Test
+    void visitSelect() {
+        //select from non table expr
+        var v = new QueryBuilder();
+        v.visitSelect(new SelectExpression(List.of(
+                new FieldExpression(null, null, "name", null),
+                new FieldExpression(null, null, "name2", null)
+        ), ConstantExpression.V0, "alias"));
+        Assertions.assertEquals("SELECT `name`, `name2` FROM (0) alias", v.getQuery());
+
+        v = new QueryBuilder();
+        v.visitSelect(new SelectExpression(List.of(
+                new FieldExpression(null, null, "name", null),
+                new FieldExpression(null, null, "name2", null)
+        ), new TableExpression("table"), "alias"));
+        Assertions.assertEquals("SELECT `name`, `name2` FROM `table` alias", v.getQuery());
+    }
+
+    @Test
+    void visitTable() {
+        var v = new QueryBuilder();
+        v.visitTable(new TableExpression("table"));
+        Assertions.assertEquals("`table`", v.getQuery());
+    }
+
+    @Test
+    void visitTernary() {
+        var v = new QueryBuilder();
+        v.visitTernary(new TernaryExpression(ConstantExpression.V0, ConstantExpression.V1, ConstantExpression.V2));
+        Assertions.assertEquals("IF(0, 1, 2)", v.getQuery());
+    }
+
+    @Test
+    void visitUnary() {
+        var v = new QueryBuilder();
+        v.visitUnary(new UnaryExpression(NullExpression.INSTANCE, UnaryExpression.Operator.NOT));
+        Assertions.assertEquals("NOT NULL", v.getQuery());
+
+        v = new QueryBuilder();
+        v.visitUnary(new UnaryExpression(new BinaryExpression(ConstantExpression.V0, ConstantExpression.V1, BinaryExpression.Operator.EQ), UnaryExpression.Operator.NOT));
+        Assertions.assertEquals("NOT (0 = 1)", v.getQuery());
+    }
+
+    @Test
+    void visitWhere() {
+        var v = new QueryBuilder();
+        v.visitWhere(new WhereExpression(ConstantExpression.V0, ConstantExpression.V1));
+        Assertions.assertEquals("0 WHERE 1", v.getQuery());
     }
 
     @Getter