Move 'unscoped' field from Engine to Statement.

See https://github.com/go-xorm/xorm/pull/175#issuecomment-61599948

engine.go

@@ -45,7 +45,6 @@ type Engine struct {
 	TZLocation *time.Location
 
 	disableGlobalCache bool
-	unscoped           bool
 }
 
 func (engine *Engine) SetDisableGlobalCache(disable bool) {
@@ -1418,8 +1417,9 @@ func (engine *Engine) FormatTime(sqlTypeName string, t time.Time) (v interface{}
 	return
 }
 
-// Disable soft delete
+// Always disable struct tag "deleted"
-func (engine *Engine) Unscoped() *Engine {
+func (engine *Engine) Unscoped() *Session {
-	engine.unscoped = true
+	session := engine.NewSession()
-	return engine
+	defer session.Close()
+	return session.Unscoped()
 }

session.go

@@ -1079,7 +1079,7 @@ func (session *Session) Find(rowsSlicePtr interface{}, condiBean ...interface{})
 	if len(condiBean) > 0 {
 		colNames, args := buildConditions(session.Engine, table, condiBean[0], true, true,
 			false, true, session.Statement.allUseBool, session.Statement.useAllCols,
-			session.Statement.mustColumnMap)
+			session.Statement.unscoped, session.Statement.mustColumnMap)
 		session.Statement.ConditionStr = strings.Join(colNames, " AND ")
 		session.Statement.BeanArgs = args
 	}
@@ -3172,7 +3172,7 @@ func (session *Session) Update(bean interface{}, condiBean ...interface{}) (int6
 	if len(condiBean) > 0 {
 		condiColNames, condiArgs = buildConditions(session.Engine, session.Statement.RefTable, condiBean[0], true, true,
 			false, true, session.Statement.allUseBool, session.Statement.useAllCols,
-			session.Statement.mustColumnMap)
+			session.Statement.unscoped, session.Statement.mustColumnMap)
 	}
 
 	var condition = ""
@@ -3376,7 +3376,7 @@ func (session *Session) Delete(bean interface{}) (int64, error) {
 	session.Statement.RefTable = table
 	colNames, args := buildConditions(session.Engine, table, bean, true, true,
 		false, true, session.Statement.allUseBool, session.Statement.useAllCols,
-		session.Statement.mustColumnMap)
+		session.Statement.unscoped, session.Statement.mustColumnMap)
 
 	var condition = ""
 	var andStr = session.Engine.dialect.AndStr()
@@ -3404,7 +3404,7 @@ func (session *Session) Delete(bean interface{}) (int64, error) {
 
 	sqlStr, sqlStrForCache := "", ""
 	argsForCache := make([]interface{}, 0, len(args) * 2)
-	if session.Engine.unscoped || table.DeletedColumn() == nil { // deleted is disabled
+	if session.Statement.unscoped || table.DeletedColumn() == nil { // tag "deleted" is disabled
 		sqlStr = fmt.Sprintf("DELETE FROM %v WHERE %v",
 			session.Engine.Quote(session.Statement.TableName()), condition)
 
@@ -3638,6 +3638,12 @@ func (s *Session) Sync2(beans ...interface{}) error {
 	return nil
 }
 
+// Always disable struct tag "deleted"
+func (session *Session) Unscoped() *Session {
+	session.Statement.Unscoped()
+	return session
+}
+
 func genCols(table *core.Table, session *Session, bean interface{}, useCol bool, includeQuote bool) ([]string, []interface{}, error) {
 	colNames := make([]string, 0)
 	args := make([]interface{}, 0)

statement.go

@@ -57,6 +57,7 @@ type Statement struct {
 	IsDistinct    bool
 	allUseBool    bool
 	checkVersion  bool
+	unscoped      bool
 	mustColumnMap map[string]bool
 	inColumns     map[string]*inParam
 	incrColumns   map[string]incrParam
@@ -91,6 +92,7 @@ func (statement *Statement) Init() {
 	statement.useAllCols = false
 	statement.mustColumnMap = make(map[string]bool)
 	statement.checkVersion = true
+	statement.unscoped = false
 	statement.inColumns = make(map[string]*inParam)
 	statement.incrColumns = make(map[string]incrParam)
 	statement.decrColumns = make(map[string]decrParam)
@@ -468,7 +470,7 @@ func buildUpdates(engine *Engine, table *core.Table, bean interface{},
 // 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,
+	includeAutoIncr bool, allUseBool bool, useAllCols bool, unscoped bool,
 	mustColumnMap map[string]bool) ([]string, []interface{}) {
 
 	colNames := make([]string, 0)
@@ -493,7 +495,7 @@ func buildConditions(engine *Engine, table *core.Table, bean interface{},
 			continue
 		}
 
-		if col.IsDeleted && !engine.unscoped { // deleted enabled
+		if col.IsDeleted && !unscoped { // tag "deleted" is enabled
 			colNames = append(colNames, fmt.Sprintf("%v IS NULL", engine.Quote(col.Name)))
 		}
 
@@ -933,6 +935,12 @@ func (statement *Statement) Having(conditions string) *Statement {
 	return statement
 }
 
+// Always disable struct tag "deleted"
+func (statement *Statement) Unscoped() *Statement {
+	statement.unscoped = true
+	return statement
+}
+
 func (statement *Statement) genColumnStr() string {
 	table := statement.RefTable
 	colNames := make([]string, 0)
@@ -1037,7 +1045,7 @@ func (statement *Statement) genGetSql(bean interface{}) (string, []interface{})
 
 	colNames, args := buildConditions(statement.Engine, table, bean, true, true,
 		false, true, statement.allUseBool, statement.useAllCols,
-		statement.mustColumnMap)
+		statement.unscoped, statement.mustColumnMap)
 
 	statement.ConditionStr = strings.Join(colNames, " "+statement.Engine.dialect.AndStr()+" ")
 	statement.BeanArgs = args
@@ -1083,7 +1091,8 @@ func (statement *Statement) genCountSql(bean interface{}) (string, []interface{}
 	statement.RefTable = table
 
 	colNames, args := buildConditions(statement.Engine, table, bean, true, true, false,
-		true, statement.allUseBool, statement.useAllCols, statement.mustColumnMap)
+		true, statement.allUseBool, statement.useAllCols,
+		statement.unscoped, statement.mustColumnMap)
 
 	statement.ConditionStr = strings.Join(colNames, " "+statement.Engine.Dialect().AndStr()+" ")
 	statement.BeanArgs = args