mirror of
https://gitee.com/johng/gf.git
synced 2024-12-05 05:37:55 +08:00
144 lines
4.3 KiB
Go
144 lines
4.3 KiB
Go
// Copyright 2017 gf Author(https://gitee.com/johng/gf). All Rights Reserved.
|
||
//
|
||
// This Source Code Form is subject to the terms of the MIT License.
|
||
// If a copy of the MIT was not distributed with this file,
|
||
// You can obtain one at https://gitee.com/johng/gf.
|
||
/*
|
||
@author wenzi1<liyz23@qq.com>
|
||
@date 20181026
|
||
说明:
|
||
1.需要导入oracle驱动: github.com/mattn/go-oci8
|
||
2.不支持save/replace方法,可以调用这2个方法估计会报错,还没测试过,(应该是可以通过oracle的merge来实现这2个功能的,还没仔细研究)
|
||
3.不支持LastInsertId方法
|
||
*/
|
||
package gdb
|
||
|
||
import (
|
||
"database/sql"
|
||
"fmt"
|
||
"gitee.com/johng/gf/g/util/gregex"
|
||
"strconv"
|
||
"strings"
|
||
)
|
||
|
||
// 数据库链接对象
|
||
type dbOracle struct {
|
||
*dbBase
|
||
}
|
||
|
||
// 创建SQL操作对象
|
||
func (db *dbOracle) Open(config *ConfigNode) (*sql.DB, error) {
|
||
var source string
|
||
if config.Linkinfo != "" {
|
||
source = config.Linkinfo
|
||
} else {
|
||
source = fmt.Sprintf("%s/%s@%s", config.User, config.Pass, config.Name)
|
||
}
|
||
if db, err := sql.Open("oci8", source); err == nil {
|
||
return db, nil
|
||
} else {
|
||
return nil, err
|
||
}
|
||
}
|
||
|
||
// 获得关键字操作符
|
||
func (db *dbOracle) getChars () (charLeft string, charRight string) {
|
||
return "\"", "\""
|
||
}
|
||
|
||
// 在执行sql之前对sql进行进一步处理
|
||
func (db *dbOracle) handleSqlBeforeExec(query string) string {
|
||
index := 0
|
||
str, _ := gregex.ReplaceStringFunc("\\?", query, func(s string) string {
|
||
index++
|
||
return fmt.Sprintf(":%d", index)
|
||
})
|
||
|
||
str, _ = gregex.ReplaceString("\"", "", str)
|
||
|
||
return db.parseSql(str)
|
||
}
|
||
|
||
//由于ORACLE中对LIMIT和批量插入的语法与MYSQL不一致,所以这里需要对LIMIT和批量插入做语法上的转换
|
||
func (db *dbOracle) parseSql(sql string) string {
|
||
//下面的正则表达式匹配出SELECT和INSERT的关键字后分别做不同的处理,如有LIMIT则将LIMIT的关键字也匹配出
|
||
patten := `^\s*(?i)(SELECT)|(INSERT)|(LIMIT\s*(\d+)\s*,\s*(\d+))`
|
||
if gregex.IsMatchString(patten, sql) == false {
|
||
fmt.Println("not matched..")
|
||
return sql
|
||
}
|
||
|
||
res, err := gregex.MatchAllString(patten, sql)
|
||
if err != nil {
|
||
fmt.Println("MatchString error.", err)
|
||
return ""
|
||
}
|
||
|
||
index := 0
|
||
keyword := strings.TrimSpace(res[index][0])
|
||
keyword = strings.ToUpper(keyword)
|
||
|
||
index++
|
||
switch keyword {
|
||
case "SELECT":
|
||
//不含LIMIT关键字则不处理
|
||
if len(res) < 2 || (strings.HasPrefix(res[index][0], "LIMIT") == false && strings.HasPrefix(res[index][0], "limit") == false) {
|
||
break
|
||
}
|
||
|
||
//取limit前面的字符串
|
||
if gregex.IsMatchString("((?i)SELECT)(.+)((?i)LIMIT)", sql) == false {
|
||
break
|
||
}
|
||
|
||
queryExpr, _ := gregex.MatchString("((?i)SELECT)(.+)((?i)LIMIT)", sql)
|
||
if len(queryExpr) != 4 || strings.EqualFold(queryExpr[1], "SELECT") == false || strings.EqualFold(queryExpr[3], "LIMIT") == false{
|
||
break
|
||
}
|
||
|
||
//取limit后面的取值范围
|
||
first, limit := 0, 0
|
||
for i := 1; i < len(res[index]); i++ {
|
||
if len(strings.TrimSpace(res[index][i])) == 0 {
|
||
continue
|
||
}
|
||
|
||
if strings.HasPrefix(res[index][i], "LIMIT") || strings.HasPrefix(res[index][i], "limit") {
|
||
first, _ = strconv.Atoi(res[index][i+1])
|
||
limit, _ = strconv.Atoi(res[index][i+2])
|
||
break
|
||
}
|
||
}
|
||
|
||
//也可以使用between,据说这种写法的性能会比between好点,里层SQL中的ROWNUM_ >= limit可以缩小查询后的数据集规模
|
||
sql = fmt.Sprintf("SELECT * FROM (SELECT GFORM.*, ROWNUM ROWNUM_ FROM (%s %s) GFORM WHERE ROWNUM <= %d) WHERE ROWNUM_ >= %d", queryExpr[1], queryExpr[2], limit, first)
|
||
case "INSERT":
|
||
//获取VALUE的值,匹配所有带括号的值,会将INSERT INTO后的值匹配到,所以下面的判断语句会判断数组长度是否小于3
|
||
valueExpr, err := gregex.MatchAllString(`(\s*\(([^\(\)]*)\))`, sql)
|
||
if err != nil {
|
||
return sql
|
||
}
|
||
|
||
//判断VALUE后的值是否有多个,只有在批量插入的时候才需要做转换,如只有1个VALUE则不需要做转换
|
||
if len(valueExpr) < 3 {
|
||
break
|
||
}
|
||
|
||
//获取INTO后面的值
|
||
tableExpr, err := gregex.MatchString(`(?i)\s*(INTO\s+\w+\(([^\(\)]*)\))`, sql)
|
||
if err != nil {
|
||
return sql
|
||
}
|
||
tableExpr[0] = strings.TrimSpace(tableExpr[0])
|
||
|
||
sql = "INSERT ALL"
|
||
for i := 1; i < len(valueExpr); i++ {
|
||
sql += fmt.Sprintf(" %s VALUES%s", tableExpr[0], strings.TrimSpace(valueExpr[i][0]))
|
||
}
|
||
sql += " SELECT 1 FROM DUAL"
|
||
|
||
default:
|
||
}
|
||
return sql
|
||
}
|