Support table alias

engine.go

@@ -560,6 +560,13 @@ func (engine *Engine) Table(tableNameOrBean interface{}) *Session {
 	return session.Table(tableNameOrBean)
 }
 
+// set the table alias
+func (engine *Engine) Alias(alias string) *Session {
+	session := engine.NewSession()
+	session.IsAutoClose = true
+	return session.Alias(alias)
+}
+
 // This method will generate "LIMIT start, limit"
 func (engine *Engine) Limit(limit int, start ...int) *Session {
 	session := engine.NewSession()
@@ -595,7 +602,7 @@ func (engine *Engine) OrderBy(order string) *Session {
 }
 
 // The join_operator should be one of INNER, LEFT OUTER, CROSS etc - this will be prepended to JOIN
-func (engine *Engine) Join(join_operator, tablename, condition string) *Session {
+func (engine *Engine) Join(join_operator string, tablename interface{}, condition string) *Session {
 	session := engine.NewSession()
 	session.IsAutoClose = true
 	return session.Join(join_operator, tablename, condition)
@@ -1246,6 +1253,13 @@ func (engine *Engine) Query(sql string, paramStr ...interface{}) (resultsSlice [
 	return session.Query(sql, paramStr...)
 }
 
+// Exec a raw sql and return records as []map[string]string
+func (engine *Engine) Q(sql string, paramStr ...interface{}) (resultsSlice []map[string]string, err error) {
+	session := engine.NewSession()
+	defer session.Close()
+	return session.Q(sql, paramStr...)
+}
+
 // Insert one or more records
 func (engine *Engine) Insert(beans ...interface{}) (int64, error) {
 	session := engine.NewSession()

session.go

@@ -134,6 +134,12 @@ func (session *Session) Table(tableNameOrBean interface{}) *Session {
 	return session
 }
 
+// set the table alias
+func (session *Session) Alias(alias string) *Session {
+	session.Statement.Alias(alias)
+	return session
+}
+
 // Method In provides a query string like "id in (1, 2, 3)"
 func (session *Session) In(column string, args ...interface{}) *Session {
 	session.Statement.In(column, args...)
@@ -257,7 +263,7 @@ func (session *Session) NoCache() *Session {
 }
 
 //The join_operator should be one of INNER, LEFT OUTER, CROSS etc - this will be prepended to JOIN
-func (session *Session) Join(join_operator, tablename, condition string) *Session {
+func (session *Session) Join(join_operator string, tablename interface{}, condition string) *Session {
 	session.Statement.Join(join_operator, tablename, condition)
 	return session
 }

statement.go

@@ -55,6 +55,7 @@ type Statement struct {
 	UseCache      bool
 	UseAutoTime   bool
 	IsDistinct    bool
+	TableAlias    string
 	allUseBool    bool
 	checkVersion  bool
 	unscoped      bool
@@ -88,6 +89,7 @@ func (statement *Statement) Init() {
 	statement.UseCache = true
 	statement.UseAutoTime = true
 	statement.IsDistinct = false
+	statement.TableAlias = ""
 	statement.allUseBool = false
 	statement.useAllCols = false
 	statement.mustColumnMap = make(map[string]bool)
@@ -105,6 +107,12 @@ func (statement *Statement) Sql(querystring string, args ...interface{}) *Statem
 	return statement
 }
 
+// set the table alias
+func (statement *Statement) Alias(alias string) *Statement {
+	statement.TableAlias = alias
+	return statement
+}
+
 // add Where statment
 func (statement *Statement) Where(querystring string, args ...interface{}) *Statement {
 	if !strings.Contains(querystring, statement.Engine.dialect.EqStr()) {
@@ -145,6 +153,9 @@ func (statement *Statement) Table(tableNameOrBean interface{}) *Statement {
 	t := v.Type()
 	if t.Kind() == reflect.String {
 		statement.AltTableName = tableNameOrBean.(string)
+		if statement.AltTableName[0] == '~' {
+			statement.AltTableName = statement.Engine.TableMapper.TableName(statement.AltTableName[1:])
+		}
 	} else if t.Kind() == reflect.Struct {
 		statement.RefTable = statement.Engine.autoMapType(v)
 	}
@@ -912,13 +923,61 @@ func (statement *Statement) Asc(colNames ...string) *Statement {
 }
 
 //The join_operator should be one of INNER, LEFT OUTER, CROSS etc - this will be prepended to JOIN
-func (statement *Statement) Join(join_operator, tablename, condition string) *Statement {
+func (statement *Statement) Join(join_operator string, tablename interface{}, condition string) *Statement {
+	var joinTable string
+	switch tablename.(type) {
+	case []string:
+		t := tablename.([]string)
+		l := len(t)
+		if l > 1 {
+			table := t[0]
+			if table[0] == '~' {
+				table = statement.Engine.TableMapper.TableName(table[1:])
+			}
+			joinTable = statement.Engine.Quote(table) + " AS " + statement.Engine.Quote(t[1])
+		} else if l == 1 {
+			table := t[0]
+			if table[0] == '~' {
+				table = statement.Engine.TableMapper.TableName(table[1:])
+			}
+			joinTable = statement.Engine.Quote(table)
+		}
+	case []interface{}:
+		t := tablename.([]interface{})
+		l := len(t)
+		table := ""
+		if l > 0 {
+			f := t[0]
+			v := rValue(f)
+			t := v.Type()
+			if t.Kind() == reflect.String {
+				table = f.(string)
+				if table[0] == '~' {
+					table = statement.Engine.TableMapper.TableName(table[1:])
+				}
+			} else if t.Kind() == reflect.Struct {
+				r := statement.Engine.autoMapType(v)
+				table = r.Name
+			}
+		}
+		if l > 1 {
+			joinTable = statement.Engine.Quote(table) + " AS " + statement.Engine.Quote(fmt.Sprintf("%v", t[1]))
+		} else if l == 1 {
+			joinTable = statement.Engine.Quote(table)
+		}
+	default:
+		t := fmt.Sprintf("%v", tablename)
+		if t[0] == '~' {
+			t = statement.Engine.TableMapper.TableName(t[1:])
+		}
+		joinTable = statement.Engine.Quote(t)
+	}
 	if statement.JoinStr != "" {
 		statement.JoinStr = statement.JoinStr + fmt.Sprintf(" %v JOIN %v ON %v", join_operator,
-			statement.Engine.Quote(tablename), condition)
+			joinTable, condition)
 	} else {
 		statement.JoinStr = fmt.Sprintf("%v JOIN %v ON %v", join_operator,
-			statement.Engine.Quote(tablename), condition)
+			joinTable, condition)
 	}
 	return statement
 }
@@ -955,16 +1014,22 @@ func (statement *Statement) genColumnStr() string {
 		}
 
 		if statement.JoinStr != "" {
-			name := statement.Engine.Quote(statement.TableName()) + "." + statement.Engine.Quote(col.Name)
+			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)
+				colNames = append(colNames, "id() AS "+name)
 			} else {
 				colNames = append(colNames, name)
 			}
 		} else {
 			name := statement.Engine.Quote(col.Name)
 			if col.IsPrimaryKey && statement.Engine.Dialect().DBType() == "ql" {
-				colNames = append(colNames, "id() as "+name)
+				colNames = append(colNames, "id() AS "+name)
 			} else {
 				colNames = append(colNames, name)
 			}
@@ -1134,6 +1199,9 @@ func (statement *Statement) genSelectSql(columnStr string) (a string) {
 		whereStr = fmt.Sprintf(" WHERE %v", statement.ConditionStr)
 	}
 	var fromStr string = " FROM " + statement.Engine.Quote(statement.TableName())
+	if statement.TableAlias != "" {
+		fromStr += " AS " + statement.Engine.Quote(statement.TableAlias)
+	}
 	if statement.JoinStr != "" {
 		fromStr = fmt.Sprintf("%v %v", fromStr, statement.JoinStr)
 	}