（承接自oracle数据库的内容）
mysql的基本操作
3306端口
启动mysql数据库：service mysqld start;
重启mysql数据库：systemctl restart mysqld;
查看状态：systemctl status mysqld;
停止mysql服务：systemctl stop mysqld;
启动mysql服务：systemctl start mysqld;
- oracle数据库中有多个用户，每个用户有多张表
- mysql数据库只有一个用户（root），有多个数据库，每个数据库下有多张表
登录mysql数据库：mysql -uroot -psyc13140;
或者：mysql -uroot -p;，然后输入密码，prevent peeping
mysql数据库CRUD
what is CRUD: create, retrieve, update, delete
create a database:
创建一个名为db1的数据库：create database mydb1;
创建一个使用utf-8字符集的数据库：create database mydb2 character set utf8;
创建一个带校验规则的mydb3数据库：create database mydb3 character set utf8 collate utf8_general_ci;
查看所有数据库：show databases;
显示创建数据库的语句信息：show create database mydb3;
修改数据库的字符集：alter database mydb1 character set utf8;
删除数据库：drop database mydb1;
mysql数据库表CRUD
由于mysql的层次结构为用户，数据库，表
所以创建数据表需要先选中库：use mydb3;
查看库中的表：show tables;
创建表：create table emp(empno int,ename varchar(20),sal int);
mysql中的数据类型：
查看表创建过程：show create table emp;
查看表的结构：desc emp;
mysql> desc emp;
+-------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| empno | int(11) | YES | | NULL | |
| ename | varchar(20) | YES | | NULL | |
| sal | int(11) | YES | | NULL | |
+-------+-------------+------+-----+---------+-------+
3 rows in set (0.00 sec)
重命名表：rename table emp to worker;
添加一个字段：alter table emp add column height double;
修改一个字段：alter table emp modify column height float;
删除一个字段：alter table emp drop column height;
修改表的字符集：alter table emp character set utf8;
删除表：drop table emp;
mysql数据库表数据CRUD
创建表：
create table emp(
id int,
name varchar(20),
sex int,
birthday date,
salary double,
hiredate date,
resume text
);
插入数据： insert into emp values(1,'daniel',1,'1999-10-19',20000,'2023-10-10','i hope so');
修改数据：update emp set salary=salary+50;
删除数据：delete from emp where name='daniel'
清空表：truncate table emp;或delete from emp;
起别名：select id,name as "姓名",salary "月薪",salary*12 年薪 from emp where id=1;
练习：
创建表：
mysql> create table student(
-> id int,
-> name varchar(20),
-> chinese int,
-> englise int,
-> math int
-> );
查询并过滤表中的重复数据：select distinct english from student;
几个查询语句：
limit和offset
select * from article limit 1,3
select * from article limit 3 OFFSET 1
上面两种写法都表示取第2，3，4三条数据
当limit后面跟两个参数的时候，第一个数表示要跳过的数量，后一位表示要取的数量，例如
select* from article limit 1,3就是跳过1条数据，从第2条数据开始取，取3条数据，也就是取2，3，4三条数据
当limit后面跟一个参数的时候，该参数表示要取的数据的数量
例如select* from article limit 3表示直接取前三条数据
当limit和offset组合使用的时候，limit后面只能有一个参数，表示要取的的数量，offset表示要跳过的数量
例如select * from article limit 3 offset 1表示跳过1条数据，从第2条数据开始取，取3条数据，也就是取2，3，4三条数据
mysql中的函数
分为3类：时间，日期，时间戳（含有时分秒的sysdate）
mysql> select now() from dual;
+---------------------+
| now() |
+---------------------+
| 2022-02-12 10:54:39 |
+---------------------+
1 row in set (0.00 sec)
mysql> select CURRENT_DATE,CURRENT_TIME,CURRENT_TIMESTAMP from dual;
+--------------+--------------+---------------------+
| CURRENT_DATE | CURRENT_TIME | CURRENT_TIMESTAMP |
+--------------+--------------+---------------------+
| 2022-02-12 | 11:02:04 | 2022-02-12 11:02:04 |
+--------------+--------------+---------------------+
1 row in set (0.00 sec)
mysql> select year(now()),month(now()),day(now()),date(now()) from dual;
+-------------+--------------+------------+-------------+
| year(now()) | month(now()) | day(now()) | date(now()) |
+-------------+--------------+------------+-------------+
| 2022 | 2 | 12 | 2022-02-12 |
+-------------+--------------+------------+-------------+
1 row in set (0.00 sec)
mysql> select date_add(now(),INTERVAL 2 year) from dual;
+---------------------------------+
| date_add(now(),INTERVAL 2 year) |
+---------------------------------+
| 2024-02-12 11:09:01 |
+---------------------------------+
1 row in set (0.00 sec)
mysql> select date_add(now(),INTERVAL -1 day) yesterday,now() today,date_add(now(),INTERVAL +1 day) tomorrow;
+---------------------+---------------------+---------------------+
| yesterday | today | tomorrow |
+---------------------+---------------------+---------------------+
| 2022-02-11 11:11:08 | 2022-02-12 11:11:08 | 2022-02-13 11:11:08 |
+---------------------+---------------------+---------------------+
1 row in set (0.00 sec)
日期函数：
字符串函数：
mysql> select date_format(now(),'%Y-%m-%d') from dual;
+-------------------------------+
| date_format(now(),'%Y-%m-%d') |
+-------------------------------+
| 2022-02-12 |
+-------------------------------+
1 row in set (0.00 sec)
mysql> select date_format(now(),'%Y-%m-%d %h:%i:%s') from dual;
+----------------------------------------+
| date_format(now(),'%Y-%m-%d %h:%i:%s') |
+----------------------------------------+
| 2022-02-12 11:22:34 |
+----------------------------------------+
1 row in set (0.00 sec)
mysql> select str_to_date('2018-11-11 8:8:8','%Y-%m-%d %h:%i:%s') from dual;
+-----------------------------------------------------+
| str_to_date('2018-11-11 8:8:8','%Y-%m-%d %h:%i:%s') |
+-----------------------------------------------------+
| 2018-11-11 08:08:08 |
+-----------------------------------------------------+
1 row in set (0.00 sec)
数学函数：
mysql> select bin(255) from dual;
+----------+
| bin(255) |
+----------+
| 11111111 |
+----------+
1 row in set (0.00 sec)
mysql> select ceiling(3.14) from dual;
+---------------+
| ceiling(3.14) |
+---------------+
| 4 |
+---------------+
1 row in set (0.00 sec)
mysql> select floor(3.14) from dual;
+-------------+
| floor(3.14) |
+-------------+
| 3 |
+-------------+
1 row in set (0.00 sec)
mysql> select conv(10,8,2) from dual;
+--------------+
| conv(10,8,2) |
+--------------+
| 1000 |
+--------------+
1 row in set (0.00 sec)
mysql> select hex(255) from dual;
+----------+
| hex(255) |
+----------+
| FF |
+----------+
1 row in set (0.00 sec)
mysql> select rand(now()) from dual;
+--------------------+
| rand(now()) |
+--------------------+
| 0.5498581822494587 |
+--------------------+
1 row in set (0.00 sec)
启动监听：lsnrctl start
多表查询
建表脚本：
create database if not exists scott character set utf8;
use scott;
create table bonus(
ename VARCHAR(10),
jod VARCHAR(10),
sal int,
comm int
);
create table dept(
deptno int not null,
dname VARCHAR(14),
loc VARCHAR(13)
);
alter table dept add constraint PK_DEPT primary key(deptno);
create table emp(
empno int not null,
ename VARCHAR(10),
job VARCHAR(9),
mgr int,
hiredate DATE,
sal int,
comm int,
deptno int
);
alter table emp add constraint PK_EMP primary key(EMPNO);
alter table emp add constraint FK_DEPTNO foreign key(DEPTNO) references dept(DEPTNO);
create table salgrade(
grade int,
losal int,
hisal int
);
insert into dept(deptno,dname,loc) values
(10,'ACCOUNTING','NEW YORK'),
(20,'RESEARCH','DALLAS'),
(30,'SALES','CHICAGO'),
(40,'DPERATIONS','BOSTON');
insert into emp(empno,ename,job,mgr,hiredate,sal,comm,deptno) values
(7369,'SMITH','CLERK',7902,'1980-12-17',800,null,20),
(7499,'ALLEN','SALESMAN',7698,'1981-02-20',1600,300,30),
(7521,'WARD','SALESMAN',7998,'1981-02-21',1250,500,30),
(7688,'JONES','MANAGER',7839,'1981-04-02',2975,null,20),
(7654,'MARTIN','SALESMAN',7698,'1981-09-28',1250,1400,30),
(7698,'BLAKE','MANAGER',7839,'1981-05-01',2880,null,30),
(7782,'CLARK','MANAGER',7839,'1981-06-09',2450,null,10),
(7788,'SCOTT','ANALYST',7566,'1987-05-23',1100,null,20),
(7839,'KING','PRESIDENT',null,'1981-11-17',5000,null,10),
(7844,'TURNER','SALESMAN',7698,'1981-09-08',1500,0,30),
(7876,'ADAMS','CLERK',7788,'1987-05-23',1100,null,20),
(7900,'JAMES','CLERK',7698,'1981-12-03',950,null,30),
(7902,'FORD','ANALYST',7566,'1981-12-03',3000,null,20),
(7934,'MILLER','CLERK',7782,'1982-01-23',1300,null,10);
insert into salgrade(grade,losal,hisal) values
(1,700,1200),
(2,1201,1400),
(3,1401,2000),
(4,2001,3000),
(5,3001,9999);
执行sql脚本：
mysql> source /home/daniel/scott.sql;
笛卡尔积：select e.*,d.* from emp e cross join dept d;
内连接：select e.*,d.* from emp e inner join dept d on e.deptno=d.deptno;，只返回满足连接条件的数据
左外连接，左边有值就显示：select e.*,d.* from emp e left outer join dept d on e.deptno=d.deptno;
MySQL left join 与 join 有所不同。 LEFT JOIN 会读取左边数据表的全部数据，即便右边表无对应数据
对于上面两张表，使用left outer join：
mysql> SELECT a.runoob_id, a.runoob_author, b.runoob_count FROM runoob_tbl a LEFT JOIN tcount_tbl b ON a.runoob_author = b.runoob_author;
+-------------+-----------------+----------------+
| a.runoob_id | a.runoob_author | b.runoob_count |
+-------------+-----------------+----------------+
| 1 | 菜鸟教程 | 10 |
| 2 | 菜鸟教程 | 10 |
| 3 | RUNOOB.COM | 20 |
| 4 | RUNOOB.COM | 20 |
| 5 | FK | NULL |
+-------------+-----------------+----------------+
5 rows in set (0.01 sec)
以上实例中使用了 LEFT JOIN，该语句会读取左边的数据表 runoob_tbl 的所有选取的字段数据，即便在右侧表 tcount_tbl中 没有对应的 runoob_author 字段值。
右外连接与之同理，右边有值就显示：select e.*,d.* from emp e right outer join dept d on e.deptno=d.deptno;
sql99中外连接取值与关系表达式=左右位置无关。取值跟from后表的书写顺序有关
全外连接：select e.*,d.* from emp e full outer join dept d on e.deptno=d.deptno;
查询每个部门员工数：select d.deptno,d.dname,count(e.deptno) from dept d,emp e where d.deptno=e.deptno group by d.deptno,d.dname;。
对于40号部门无法正常显示，使用左外连接：select d.deptno,d.dname,count(e.deptno) from dept d left outer join emp e on d.deptno=e.deptno group by d.deptno,d.dname;
修改数据：update dept set dname='OPERATIONS' where deptno=40;
自连接：
查询员工的老板：
select concat(e.ename,'\'s boss is ',ifnull(b.ename,'himself')) info
from emp e left outer join emp b
on e.mgr=b.empno;
约束
删除主键约束：alter table table_name drop primary key;
约束举例：
mysql> create table myclass(
-> id INT(11) primary key auto_increment,
-> name varchar(20) unique
-> );
Query OK, 0 rows affected (0.21 sec)
mysql> create table student(
-> id INT(11) primary key auto_increment,
-> name varchar(20) unique,
-> passwd varchar(15) not null,
-> classid INT(11),
-> constraint stu_classid_FK foreign key(classid) references myclass(id)
-> );
Query OK, 0 rows affected (0.01 sec)
查看字符集：show variables like 'character%';
i18n=internationalization
C程序连接mysql数据库
manual文档：https://dev.mysql/doc/refman/8.0/en/
重点关注：
Connectors and APIs
Data Types
Functions and Operators
SQL Statements
Language Structure
MySQL Programs
等章节
安装mysqlclient：sudo apt-get install libmysqlclient-dev
查找头文件和库的位置：locate mysql.h
头文件和库目录：
daniel@ubuntu:~/project/c/demo$ locate mysql.h
/usr/include/mysql/mysql.h
daniel@ubuntu:~/project/c/demo$ locate libmysqlclient.so
/usr/lib/x86_64-linux-gnu/libmysqlclient.so
/usr/lib/x86_64-linux-gnu/libmysqlclient.so.20
/usr/lib/x86_64-linux-gnu/libmysqlclient.so.20.3.24
测试程序：
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <mysql/mysql.h>
#define HOST "192.168.37.131"
#define USER "root"
#define PWD "syc13140"
#define DB "scott"
#define error_msg(msg) \
printf("error:%s: in function %s at line %d, msg:%s\n",__FILE__,__func__,__LINE__,msg);
int main(void ){
MYSQL* mysql=mysql_init(NULL);
if(NULL==mysql){
error_msg("mysql_init failed");
exit(1);
}
mysql=mysql_real_connect(mysql,HOST,USER,PWD,DB,0,NULL,0);
if(NULL==mysql){
error_msg("mysql_real_connect() failed");
exit(1);
}
mysql_close(mysql);
return 0;
}
插入数据：
int main(void ){
MYSQL* mysql=mysql_init(NULL);
if(NULL==mysql){
error_msg("mysql_init() failed");
exit(1);
}
mysql=mysql_real_connect(mysql,HOST,USER,PWD,DB,0,NULL,0);
if(NULL==mysql){
error_msg("mysql_real_connect() failed");
exit(1);
}
char query_str[128]="insert into dept values(1,'1name','1loc')";
int ret=mysql_query(mysql,query_str);
if(0!=ret){
error_msg("mysql_query() failed");
exit(1);
}
mysql_close(mysql);
return 0;
}
makefile编写：
SRC:=$(wildcard *.c)
OBJ:=$(patsubst %.c,%,$(SRC))
LIB:= -l mysqlclient
INC:=-I /usr/include
all:$(OBJ)
%:%.c
gcc $< -o $@ $(LIB) $(INC)
.PHONY:clean
clean:
rm -rf $(OBJ)
删除数据：
const char* delstr="delete from dept where deptno=1";
int ret=mysql_query(mysql,delstr);
if(0!=ret){
error_msg("mysql_query() failed");
exit(1);
}
更新数据：
const char* update_str="update dept set dname='1NAME',loc='1LOC' where deptno=1";
int ret=mysql_query(mysql,update_str);
if(0!=ret){
error_msg("mysql_query() failed");
exit(1);
}
mysql_error()函数使用：
API：
const char* mysql_error(MYSQL* mysql);
使用：
const char* insert_query="insert into dept values(1,'1name','1loc')";
int ret=mysql_query(mysql,insert_query);
if(0!=ret){
error_msg(mysql_error(mysql));
exit(1);
}
这条数据已经存在，会造成主键冲突的错误：
daniel@ubuntu:~/project/c/demo$ ./mysql_demo
error:mysql_demo.c: in function main at line 32, msg:Duplicate entry '1' for key 'PRIMARY'
mysql_store_result获取结果集：
客户端处理结果集的方式有两种。一种方式是，通过调用mysql_store_result()，一次性地检索整个结果集。该函数能从服务器获得查询返回的所有行，并将它们保存在客户端。第二种方式是针对客户端的，通过调用mysql_use_result()，对“按行”结果集检索进行初始化处理。该函数能初始化检索结果，但不能从服务器获得任何实际行。
在这两种情况下，均能通过调用mysql_fetch_row()访问行。通过mysql_store_result()，mysql_fetch_row()能够访问以前从服务器获得的行。通过mysql_use_result()，mysql_fetch_row()能够实际地检索来自服务器的行。通过调用mysql_fetch_lengths()，能获得关于各行中数据大小的信息。
完成结果集操作后，请调用mysql_free_result()释放结果集使用的内存。
这两种检索机制是互补的。客户端程序应选择最能满足其要求的方法。实际上，客户端最常使用的是mysql_store_result()。
MYSQL_RES* mysql_store_result(MYSQL* mysql);
MYSQL_ROW mysql_fetch_row(MYSQL_RES* result);
unsigned long *mysql_fetch_lengths(MYSQL_RES* result);
获取结果集并查看其行列数：
int main(void ){
//获取句柄
MYSQL* mysql=mysql_init(NULL);
if(NULL==mysql){
error_msg("mysql_init failed");
exit(1);
}
//连接到服务器
mysql=mysql_real_connect(mysql,HOST,USER,PWD,DB,0,NULL,0);
if(NULL==mysql){
error_msg("mysql_real_connect failed");
exit(1);
}
//query
const char* query_str="select * from dept";
int ret=mysql_query(mysql,query_str);
if(0!=ret){
error_msg(mysql_error(mysql));
exit(1);
}
//获取结果集
MYSQL_RES* res=mysql_store_result(mysql);
if(NULL==res){
error_msg(mysql_error(mysql));
exit(1);
}
//查看结果集行列数
printf("there are %llu rows in the table\n",mysql_num_rows(res));
printf("there are %u columns in the table\n", mysql_num_fields(res));
//关闭连接
mysql_close(mysql);
mysql_free_result(res);
return 0;
}
遍历结果集：
int field_num = mysql_num_fields(res);
MYSQL_ROW row = NULL;
//每次循环获取一行
while (row = mysql_fetch_row(res)) {
//遍历每一个字段
for (int i = 0; i < field_num; ++i) {
printf("%-10s ", row[i]);
}
printf("\n");
}
获取表头数据信息：
//MYSQL_FIELD *mysql_fetch_fields(MYSQL_RES *result);
int field_num = mysql_num_fields(res);
//获取表头数据
MYSQL_FIELD* field = mysql_fetch_fields(res);
for (int i = 0; i < field_num; ++i) {
printf("%12s", field[i].name);
}
printf("\n");
简单客户端的实现：
#include <mysql/mysql.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define HOST "192.168.37.131"
#define USER "root"
#define PWD "syc13140"
#define DB "scott"
#define SIZE 1024
#define error_msg(msg) \
printf("error:%s: in function %s at line %d, msg:%s\n", __FILE__, __func__, __LINE__, msg);
int print_selected_result(MYSQL_RES* res) {
if (NULL != res) {
int field_num = mysql_num_fields(res);
MYSQL_ROW row = NULL;
//获取表头数据
MYSQL_FIELD* field = mysql_fetch_fields(res);
for (int i = 0; i < field_num; ++i) {
printf("%12s", field[i].name);
}
printf("\n");
//每次循环获取一行
while (row = mysql_fetch_row(res)) {
//遍历每一个字段
for (int i = 0; i < field_num; ++i) {
printf("%12s", row[i]);
}
printf("\n");
}
mysql_free_result(res);
}
return 0;
}
int main(void) {
MYSQL* mysql = mysql_init(NULL);
if (NULL == mysql) {
error_msg("mysql_init failed");
exit(1);
}
mysql = mysql_real_connect(mysql, HOST, USER, PWD, DB, 0, NULL, 0);
if (NULL == mysql) {
error_msg("mysql_real_connect failed");
exit(1);
}
// system("clear");
//执行sql语句
char buf[SIZE];
while (1) {
memset(buf, 0, SIZE);
write(STDOUT_FILENO, "mysql> ", strlen("mysql> "));
//读取sql命令
int n = read(STDIN_FILENO, buf, SIZE);
if (1 == n) {
continue;
}
if (strncasecmp("quit", buf, 4) == 0 || strncasecmp("exit", buf, 4) == 0) {
printf("Bye\n");
break;
}
//查询
buf[strlen(buf) - 1] = 0; //;->0
int ret = mysql_query(mysql, buf);
if (0 != ret) {
error_msg(mysql_error(mysql));
continue;
}
//获取结果集
MYSQL_RES* res = mysql_store_result(mysql);
if (NULL == res) {
if (mysql_field_count(mysql) == 0) { // create, updata, delete
printf("Query OK, %llu row affected\n", mysql_affected_rows(mysql));
} else { // error
error_msg(mysql_error(mysql));
continue;
}
} else { // retrieve
print_selected_result(res);
}
}
mysql_close(mysql);
return 0;
}
mysql预处理语句
绝大多数情况下，某需求某一条 SQL 语句可能会被反复调用执行，或者每次执行的时候只有个别的值不同（比如 select 的 where 子句值不同，update 的 set 子句值不同，insert 的 values 值不同）。如果每次都需要经过上面的词法语义解析、语句优化、制定执行计划等，则效率就明显不行了。
所谓预编译语句就是将此类 SQL 语句中的值用占位符替代，可以视为将 SQL 语句模板化或者说参数化，一般称这类语句叫Prepared Statements。
预编译语句的优势在于归纳为：一次编译、多次运行，省去了解析优化等过程；此外预编译语句能防止 SQL 注入。
语法：
prepare stmt_name from "preparable_stmt";
execute stmt_name [using @var1_name[,using @var2_name]...];
drop prepare stmt_name;
实例：
mysql> prepare stmt1 from "select sqrt(pow(?,2)+pow(?,2)) as hypotenuse";
Query OK, 0 rows affected (0.00 sec)
Statement prepared
mysql> set @a=3;
Query OK, 0 rows affected (0.00 sec)
mysql> set @b=4;
Query OK, 0 rows affected (0.00 sec)
mysql> execute stmt1 using @a,@b;
+------------+
| hypotenuse |
+------------+
| 5 |
+------------+
1 row in set (0.00 sec)
C语言实现：
int main(void) {
MYSQL* mysql = mysql_init(NULL);
mysql = mysql_real_connect(mysql, HOST, USER, PWD, DB, 0, NULL, 0);
//准备预处理语句
MYSQL_STMT* stmt = mysql_stmt_init(mysql);
const char* stmt_str = "select sqrt(pow(?,2)+pow(?,2)) as hypotenuse";
int ret = mysql_stmt_prepare(stmt, stmt_str, strlen(stmt_str));
//准备并绑定参数
int para[2] = {3, 4};
MYSQL_BIND bind_para[2];
for (int i = 0; i < 2; ++i) {
bind_para[i].buffer_type = MYSQL_TYPE_LONG;
bind_para[i].buffer = (char*)(para + i);
bind_para[i].is_null = 0;
bind_para[i].length = 0;
}
mysql_stmt_bind_param(stmt, bind_para);
//执行
ret = mysql_stmt_execute(stmt);
//查看影响到的行数
int affected_rows = mysql_stmt_affected_rows(stmt);
fprintf(stdout, " total affected rows: %lu\n", (unsigned long)affected_rows);
mysql_stmt_close(stmt);
mysql_close(mysql);
return 0;
}
触发器
在某个表发生更改时自动处理的一系列动作，可以响应以下三种语句：
DELETE
INSERT
UPDATE
因此一个表最多6个触发器，分别位于这三条语句之前和之后
创建触发器：
CREATE TRIGGER newproduct AFTER INSERT ON products
FOR EACH ROW SELECT "Product added";
删除触发器：
DROP TRIGGER newproduct;
使用INSERT触发器实时显示AUTO_INCREMENT后的值：
CREATE TRIGGER neworder AFTER INSERT ON orders
FOR EACH ROW SELECT NEW.order_num;
使用DELETE触发器将被删除的行保存到存档表中：
CREATE TRIGGER deleteorder BEFORE DELETE ON orders
FOR EACH ROW
BEGIN
INSERT INTO archive_order(order_num,order_date,cust_id)
VALUES(OLD.order_num,OLD.order_date,OLD.cust_id);
END;
使用UPDATE触发器进行数据检查：
CREATE UPDATE TRIGGER updatevendor BEFORE UPDATE ON vendors
FOR EACH ROW SET NEW.vend_state=Upper(NEW.vend_state);
mysql事务
设置自动提交和手动提交：
set autocommit=0;
set autocommit=1;
C语言实现：
//开启事务并设置为手动提交
int mysql_OperationTran(MYSQL* mysql) {
if (NULL != mysql) {
mysql_query(mysql, "start transaction");
mysql_query(mysql, "set autocommit=0");
return 0;
}
return 1;
}
//手动提交
int mysql_Commit(MYSQL* mysql) {
if (NULL != mysql) {
mysql_query(mysql, "commit");
return 0;
}
return 1;
}
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