diff --git a/engine.go b/engine.go
index ee7cb7bc..b7c39492 100644
--- a/engine.go
+++ b/engine.go
@@ -929,8 +929,16 @@ func (engine *Engine) mapType(v reflect.Value) *core.Table {
 		fieldType := fieldValue.Type()
 
 		if ormTagStr != "" {
-			col = &core.Column{FieldName: t.Field(i).Name, Nullable: true, IsPrimaryKey: false,
-				IsAutoIncrement: false, MapType: core.TWOSIDES, Indexes: make(map[string]bool)}
+			col = &core.Column{
+				FieldName:       t.Field(i).Name,
+				TableName:       table.Name,
+				Nullable:        true,
+				IsPrimaryKey:    false,
+				IsAutoIncrement: false,
+				MapType:         core.TWOSIDES,
+				Indexes:         make(map[string]bool),
+			}
+
 			tags := splitTag(ormTagStr)
 
 			if len(tags) > 0 {
@@ -952,6 +960,11 @@ func (engine *Engine) mapType(v reflect.Value) *core.Table {
 					case reflect.Struct:
 						parentTable := engine.mapType(fieldValue)
 						for _, col := range parentTable.Columns() {
+							if t.Field(i).Anonymous {
+								col.TableName = parentTable.Name
+							} else {
+								col.TableName = engine.TableMapper.Obj2Table(t.Field(i).Name)
+							}
 							col.FieldName = fmt.Sprintf("%v.%v", t.Field(i).Name, col.FieldName)
 							table.AddColumn(col)
 						}
@@ -1133,6 +1146,7 @@ func (engine *Engine) mapType(v reflect.Value) *core.Table {
 			col = core.NewColumn(engine.ColumnMapper.Obj2Table(t.Field(i).Name),
 				t.Field(i).Name, sqlType, sqlType.DefaultLength,
 				sqlType.DefaultLength2, true)
+			col.TableName = table.Name
 		}
 		if col.IsAutoIncrement {
 			col.Nullable = false
diff --git a/session.go b/session.go
index 27ebf2da..f29d8201 100644
--- a/session.go
+++ b/session.go
@@ -1044,8 +1044,10 @@ func (session *Session) Get(bean interface{}) (bool, error) {
 	var sqlStr string
 	var args []interface{}
 
+	session.Statement.OutTable = session.Engine.TableInfo(bean)
+
 	if session.Statement.RefTable == nil {
-		session.Statement.RefTable = session.Engine.TableInfo(bean)
+		session.Statement.RefTable = session.Statement.OutTable
 	}
 
 	if session.Statement.RawSQL == "" {
@@ -1139,42 +1141,39 @@ func (session *Session) Find(rowsSlicePtr interface{}, condiBean ...interface{})
 
 	sliceElementType := sliceValue.Type().Elem()
 	var table *core.Table
-	if session.Statement.RefTable == nil {
-		if sliceElementType.Kind() == reflect.Ptr {
-			if sliceElementType.Elem().Kind() == reflect.Struct {
-				pv := reflect.New(sliceElementType.Elem())
-				table = session.Engine.autoMapType(pv.Elem())
-			} else {
-				return errors.New("slice type")
-			}
-		} else if sliceElementType.Kind() == reflect.Struct {
-			pv := reflect.New(sliceElementType)
+
+	if sliceElementType.Kind() == reflect.Ptr {
+		if sliceElementType.Elem().Kind() == reflect.Struct {
+			pv := reflect.New(sliceElementType.Elem())
 			table = session.Engine.autoMapType(pv.Elem())
 		} else {
 			return errors.New("slice type")
 		}
-		session.Statement.RefTable = table
+	} else if sliceElementType.Kind() == reflect.Struct {
+		pv := reflect.New(sliceElementType)
+		table = session.Engine.autoMapType(pv.Elem())
 	} else {
-		table = session.Statement.RefTable
+		return errors.New("slice type")
+	}
+
+	session.Statement.OutTable = table
+
+	if session.Statement.RefTable == nil {
+		session.Statement.RefTable = table
 	}
 
-	var addedTableName = (len(session.Statement.JoinStr) > 0)
 	if !session.Statement.noAutoCondition && len(condiBean) > 0 {
-		colNames, args := session.Statement.buildConditions(table, condiBean[0], true, true, false, true, addedTableName)
+		colNames, args := session.Statement.buildConditions(
+			table, condiBean[0], true, true, false, true, session.Statement.needTableName())
+
 		session.Statement.ConditionStr = strings.Join(colNames, " AND ")
 		session.Statement.BeanArgs = args
 	} else {
 		// !oinume! Add "<col> IS NULL" to WHERE whatever condiBean is given.
 		// See https://github.com/go-xorm/xorm/issues/179
-		if col := table.DeletedColumn(); col != nil && !session.Statement.unscoped { // tag "deleted" is enabled
-			var colName = session.Engine.Quote(col.Name)
-			if addedTableName {
-				var nm = session.Statement.TableName()
-				if len(session.Statement.TableAlias) > 0 {
-					nm = session.Statement.TableAlias
-				}
-				colName = session.Engine.Quote(nm) + "." + colName
-			}
+		if col := table.DeletedColumn(); col != nil && !session.Statement.unscoped {
+			// tag "deleted" is enabled
+			var colName = session.Statement.colName(col, session.Statement.TableName())
 			session.Statement.ConditionStr = fmt.Sprintf("(%v IS NULL OR %v = '0001-01-01 00:00:00')",
 				colName, colName)
 		}
@@ -1183,28 +1182,7 @@ func (session *Session) Find(rowsSlicePtr interface{}, condiBean ...interface{})
 	var sqlStr string
 	var args []interface{}
 	if session.Statement.RawSQL == "" {
-		var columnStr = session.Statement.ColumnStr
-		if len(session.Statement.selectStr) > 0 {
-			columnStr = session.Statement.selectStr
-		} else {
-			if session.Statement.JoinStr == "" {
-				if columnStr == "" {
-					if session.Statement.GroupByStr != "" {
-						columnStr = session.Statement.Engine.Quote(strings.Replace(session.Statement.GroupByStr, ",", session.Engine.Quote(","), -1))
-					} else {
-						columnStr = session.Statement.genColumnStr()
-					}
-				}
-			} else {
-				if columnStr == "" {
-					if session.Statement.GroupByStr != "" {
-						columnStr = session.Statement.Engine.Quote(strings.Replace(session.Statement.GroupByStr, ",", session.Engine.Quote(","), -1))
-					} else {
-						columnStr = "*"
-					}
-				}
-			}
-		}
+		columnStr := session.Statement.genColumnStr()
 
 		session.Statement.Params = append(session.Statement.joinArgs, append(session.Statement.Params, session.Statement.BeanArgs...)...)
 
diff --git a/statement.go b/statement.go
index 3dd5c60c..214906fa 100644
--- a/statement.go
+++ b/statement.go
@@ -40,6 +40,7 @@ type exprParam struct {
 // Statement save all the sql info for executing SQL
 type Statement struct {
 	RefTable        *core.Table
+	OutTable        *core.Table
 	Engine          *Engine
 	Start           int
 	LimitN          int
@@ -54,6 +55,7 @@ type Statement struct {
 	ColumnStr       string
 	selectStr       string
 	columnMap       map[string]bool
+	tableMap        map[string]bool
 	useAllCols      bool
 	OmitStr         string
 	ConditionStr    string
@@ -85,6 +87,7 @@ type Statement struct {
 // Init reset all the statment's fields
 func (statement *Statement) Init() {
 	statement.RefTable = nil
+	statement.OutTable = nil
 	statement.Start = 0
 	statement.LimitN = 0
 	statement.WhereStr = ""
@@ -98,6 +101,7 @@ func (statement *Statement) Init() {
 	statement.ColumnStr = ""
 	statement.OmitStr = ""
 	statement.columnMap = make(map[string]bool)
+	statement.tableMap = make(map[string]bool)
 	statement.ConditionStr = ""
 	statement.AltTableName = ""
 	statement.IdParam = nil
@@ -141,7 +145,14 @@ func (statement *Statement) Sql(querystring string, args ...interface{}) *Statem
 
 // Alias set the table alias
 func (statement *Statement) Alias(alias string) *Statement {
+	if statement.TableName() != "" {
+		statement.tableMapDelete(statement.TableName())
+	}
+	if statement.TableAlias != "" {
+		statement.tableMapDelete(statement.TableAlias)
+	}
 	statement.TableAlias = alias
+	statement.tableMapAdd(alias)
 	return statement
 }
 
@@ -190,6 +201,9 @@ func (statement *Statement) Or(querystring string, args ...interface{}) *Stateme
 
 // Table tempororily set table name, the parameter could be a string or a pointer of struct
 func (statement *Statement) Table(tableNameOrBean interface{}) *Statement {
+	if statement.TableName() != "" {
+		statement.tableMapDelete(statement.TableName())
+	}
 	v := rValue(tableNameOrBean)
 	t := v.Type()
 	if t.Kind() == reflect.String {
@@ -197,6 +211,7 @@ func (statement *Statement) Table(tableNameOrBean interface{}) *Statement {
 	} else if t.Kind() == reflect.Struct {
 		statement.RefTable = statement.Engine.autoMapType(v)
 	}
+	statement.tableMapAdd(statement.TableName())
 	return statement
 }
 
@@ -440,21 +455,46 @@ func (statement *Statement) needTableName() bool {
 }
 
 func (statement *Statement) colName(col *core.Column, tableName string) string {
-	if statement.needTableName() {
-		var nm = tableName
-		if len(statement.TableAlias) > 0 {
-			nm = statement.TableAlias
+	return buildColName(statement.Engine, col, tableName, statement.TableAlias,
+		statement.outTableName(), statement.needTableName(), statement.tableMap)
+}
+
+func buildColName(engine *Engine, col *core.Column,
+	mainTableName, mainTableAlias, outTableName string, needTableName bool,
+	knownTables map[string]bool) string {
+	var colTable string
+
+	if needTableName {
+		var mainTable string
+
+		if len(mainTableAlias) > 0 {
+			mainTable = mainTableAlias
+		} else {
+			mainTable = mainTableName
+		}
+
+		if isKnownTable(engine, knownTables, mainTable, col.TableName) {
+			colTable = col.TableName
+		} else if isKnownTable(engine, knownTables, mainTable, outTableName) {
+			colTable = outTableName
+		} else {
+			colTable = ""
 		}
-		return statement.Engine.Quote(nm) + "." + statement.Engine.Quote(col.Name)
 	}
-	return statement.Engine.Quote(col.Name)
+
+	if colTable != "" {
+		return engine.Quote(colTable) + "." + engine.Quote(col.Name)
+	} else {
+		return engine.Quote(col.Name)
+	}
 }
 
 // Auto generating conditions according a struct
 func buildConditions(engine *Engine, table *core.Table, bean interface{},
 	includeVersion bool, includeUpdated bool, includeNil bool,
 	includeAutoIncr bool, allUseBool bool, useAllCols bool, unscoped bool,
-	mustColumnMap map[string]bool, tableName, aliasName string, addedTableName bool) ([]string, []interface{}) {
+	mustColumnMap map[string]bool, tableName, aliasName, outTableName string,
+	addedTableName bool, knownTables map[string]bool) ([]string, []interface{}) {
 	var colNames []string
 	var args = make([]interface{}, 0)
 	for _, col := range table.Columns() {
@@ -475,16 +515,8 @@ func buildConditions(engine *Engine, table *core.Table, bean interface{},
 			continue
 		}
 
-		var colName string
-		if addedTableName {
-			var nm = tableName
-			if len(aliasName) > 0 {
-				nm = aliasName
-			}
-			colName = engine.Quote(nm) + "." + engine.Quote(col.Name)
-		} else {
-			colName = engine.Quote(col.Name)
-		}
+		colName := buildColName(
+			engine, col, tableName, aliasName, outTableName, addedTableName, knownTables)
 
 		fieldValuePtr, err := col.ValueOf(bean)
 		if err != nil {
@@ -688,6 +720,13 @@ func (statement *Statement) TableName() string {
 	return ""
 }
 
+func (statement *Statement) outTableName() string {
+	if statement.OutTable != nil {
+		return statement.OutTable.Name
+	}
+	return ""
+}
+
 // Id generate "where id = ? " statment or for composite key "where key1 = ? and key2 = ?"
 func (statement *Statement) Id(id interface{}) *Statement {
 	idValue := reflect.ValueOf(id)
@@ -979,12 +1018,15 @@ func (statement *Statement) Join(joinOP string, tablename interface{}, condition
 		fmt.Fprintf(&buf, "%v JOIN ", joinOP)
 	}
 
+	var refName string
 	switch tablename.(type) {
 	case []string:
 		t := tablename.([]string)
 		if len(t) > 1 {
+			refName = t[1]
 			fmt.Fprintf(&buf, "%v AS %v", statement.Engine.Quote(t[0]), statement.Engine.Quote(t[1]))
 		} else if len(t) == 1 {
+			refName = t[0]
 			fmt.Fprintf(&buf, statement.Engine.Quote(t[0]))
 		}
 	case []interface{}:
@@ -1003,18 +1045,22 @@ func (statement *Statement) Join(joinOP string, tablename interface{}, condition
 			}
 		}
 		if l > 1 {
+			refName = fmt.Sprintf("%v", t[1])
 			fmt.Fprintf(&buf, "%v AS %v", statement.Engine.Quote(table),
-				statement.Engine.Quote(fmt.Sprintf("%v", t[1])))
+				statement.Engine.Quote(refName))
 		} else if l == 1 {
+			refName = table
 			fmt.Fprintf(&buf, statement.Engine.Quote(table))
 		}
 	default:
-		fmt.Fprintf(&buf, statement.Engine.Quote(fmt.Sprintf("%v", tablename)))
+		refName = fmt.Sprintf("%v", tablename)
+		fmt.Fprintf(&buf, statement.Engine.Quote(refName))
 	}
 
 	fmt.Fprintf(&buf, " ON %v", condition)
 	statement.JoinStr = buf.String()
 	statement.joinArgs = append(statement.joinArgs, args...)
+	statement.tableMap[statement.Engine.Quote(strings.ToLower(refName))] = true
 	return statement
 }
 
@@ -1037,7 +1083,23 @@ func (statement *Statement) Unscoped() *Statement {
 }
 
 func (statement *Statement) genColumnStr() string {
+	if len(statement.selectStr) > 0 {
+		return statement.selectStr
+	}
+
+	if len(statement.ColumnStr) > 0 {
+		return statement.ColumnStr
+	}
+
+	if len(statement.GroupByStr) > 0 {
+		return statement.Engine.Quote(
+			strings.Replace(statement.GroupByStr, ",", statement.Engine.Quote(","), -1))
+	}
+
 	table := statement.RefTable
+	if statement.OutTable != nil {
+		table = statement.OutTable
+	}
 	colNames := make([]string, 0)
 	for _, col := range table.Columns() {
 		if statement.OmitStr != "" {
@@ -1049,26 +1111,12 @@ func (statement *Statement) genColumnStr() string {
 			continue
 		}
 
-		if statement.JoinStr != "" {
-			var name string
-			if statement.TableAlias != "" {
-				name = statement.Engine.Quote(statement.TableAlias)
-			} else {
-				name = statement.Engine.Quote(statement.TableName())
-			}
-			name += "." + statement.Engine.Quote(col.Name)
-			if col.IsPrimaryKey && statement.Engine.Dialect().DBType() == "ql" {
-				colNames = append(colNames, "id() AS "+name)
-			} else {
-				colNames = append(colNames, name)
-			}
+		name := statement.colName(col, statement.TableName())
+
+		if col.IsPrimaryKey && statement.Engine.Dialect().DBType() == "ql" {
+			colNames = append(colNames, "id() AS "+name)
 		} else {
-			name := statement.Engine.Quote(col.Name)
-			if col.IsPrimaryKey && statement.Engine.Dialect().DBType() == "ql" {
-				colNames = append(colNames, "id() AS "+name)
-			} else {
-				colNames = append(colNames, name)
-			}
+			colNames = append(colNames, name)
 		}
 	}
 	return strings.Join(colNames, ", ")
@@ -1135,38 +1183,15 @@ func (statement *Statement) genGetSql(bean interface{}) (string, []interface{})
 		table = statement.RefTable
 	}
 
-	var addedTableName = (len(statement.JoinStr) > 0)
-
 	if !statement.noAutoCondition {
-		colNames, args := statement.buildConditions(table, bean, true, true, false, true, addedTableName)
+		colNames, args := statement.buildConditions(
+			table, bean, true, true, false, true, statement.needTableName())
 
 		statement.ConditionStr = strings.Join(colNames, " "+statement.Engine.dialect.AndStr()+" ")
 		statement.BeanArgs = args
 	}
 
-	var columnStr string = statement.ColumnStr
-	if len(statement.selectStr) > 0 {
-		columnStr = statement.selectStr
-	} else {
-		// TODO: always generate column names, not use * even if join
-		if len(statement.JoinStr) == 0 {
-			if len(columnStr) == 0 {
-				if len(statement.GroupByStr) > 0 {
-					columnStr = statement.Engine.Quote(strings.Replace(statement.GroupByStr, ",", statement.Engine.Quote(","), -1))
-				} else {
-					columnStr = statement.genColumnStr()
-				}
-			}
-		} else {
-			if len(columnStr) == 0 {
-				if len(statement.GroupByStr) > 0 {
-					columnStr = statement.Engine.Quote(strings.Replace(statement.GroupByStr, ",", statement.Engine.Quote(","), -1))
-				} else {
-					columnStr = "*"
-				}
-			}
-		}
-	}
+	columnStr := statement.genColumnStr()
 
 	statement.attachInSql() // !admpub!  fix bug:Iterate func missing "... IN (...)"
 	return statement.genSelectSQL(columnStr), append(append(statement.joinArgs, statement.Params...), statement.BeanArgs...)
@@ -1195,7 +1220,7 @@ func (s *Statement) genAddUniqueStr(uqeName string, cols []string) (string, []in
 
 func (statement *Statement) buildConditions(table *core.Table, bean interface{}, includeVersion bool, includeUpdated bool, includeNil bool, includeAutoIncr bool, addedTableName bool) ([]string, []interface{}) {
 	return buildConditions(statement.Engine, table, bean, includeVersion, includeUpdated, includeNil, includeAutoIncr, statement.allUseBool, statement.useAllCols,
-		statement.unscoped, statement.mustColumnMap, statement.TableName(), statement.TableAlias, addedTableName)
+		statement.unscoped, statement.mustColumnMap, statement.TableName(), statement.TableAlias, statement.outTableName(), addedTableName, statement.tableMap)
 }
 
 func (statement *Statement) genCountSql(bean interface{}) (string, []interface{}) {
@@ -1347,3 +1372,24 @@ func (statement *Statement) processIdParam() {
 		}
 	}
 }
+
+func (statement *Statement) tableMapAdd(table string) {
+	tableName := statement.Engine.Quote(strings.ToLower(table))
+	statement.tableMap[tableName] = true
+}
+
+func (statement *Statement) tableMapDelete(table string) {
+	tableName := statement.Engine.Quote(strings.ToLower(table))
+	delete(statement.tableMap, tableName)
+}
+
+func isKnownTable(engine *Engine, tableMap map[string]bool, mainTable, table string) bool {
+	if len(table) > 0 {
+		cm := engine.Quote(strings.ToLower(mainTable))
+		ct := engine.Quote(strings.ToLower(table))
+		if ct == cm || tableMap[ct] {
+			return true
+		}
+	}
+	return false
+}