gitroast/vendor/github.com/go-xorm/xorm/session_exist.go

88 lines
2.0 KiB
Go

// Copyright 2017 The Xorm Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package xorm
import (
"errors"
"fmt"
"reflect"
"github.com/go-xorm/builder"
"github.com/go-xorm/core"
)
// Exist returns true if the record exist otherwise return false
func (session *Session) Exist(bean ...interface{}) (bool, error) {
defer session.resetStatement()
if session.isAutoClose {
defer session.Close()
}
var sqlStr string
var args []interface{}
var err error
if session.statement.RawSQL == "" {
if len(bean) == 0 {
tableName := session.statement.TableName()
if len(tableName) <= 0 {
return false, ErrTableNotFound
}
if session.statement.cond.IsValid() {
condSQL, condArgs, err := builder.ToSQL(session.statement.cond)
if err != nil {
return false, err
}
sqlStr = fmt.Sprintf("SELECT * FROM %s WHERE %s LIMIT 1", tableName, condSQL)
args = condArgs
} else {
sqlStr = fmt.Sprintf("SELECT * FROM %s LIMIT 1", tableName)
args = []interface{}{}
}
} else {
beanValue := reflect.ValueOf(bean[0])
if beanValue.Kind() != reflect.Ptr {
return false, errors.New("needs a pointer")
}
if beanValue.Elem().Kind() == reflect.Struct {
if err := session.statement.setRefValue(beanValue.Elem()); err != nil {
return false, err
}
}
if len(session.statement.TableName()) <= 0 {
return false, ErrTableNotFound
}
session.statement.Limit(1)
sqlStr, args, err = session.statement.genGetSQL(bean[0])
if err != nil {
return false, err
}
}
} else {
sqlStr = session.statement.RawSQL
args = session.statement.RawParams
}
session.queryPreprocess(&sqlStr, args...)
var rawRows *core.Rows
if session.isAutoCommit {
_, rawRows, err = session.innerQuery(sqlStr, args...)
} else {
rawRows, err = session.tx.Query(sqlStr, args...)
}
if err != nil {
return false, err
}
defer rawRows.Close()
return rawRows.Next(), nil
}