下面贴出我在实际工作中遇到mysql操作数据表的sql命令,如有不对的地方,请多指教:
c++链接mysql头文件命令
g++ is_in_polygon.cpp -o is_in_polygon -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
eclipse 设置mysql
project->setting->properties->tool settings->libraries-libraries(l) write into:mysqlclient. project->properties->tool settings->libraries->libraries search path write into:/usr/lib/mysql.
project->properties->c/c++ build->environment->cplus_include_path and c_include_path 加入:/usr/include/mysql
建立数据表
use test;
create table test_info (
id integer not null,
content varchar(64) not null,
primary key (id)
);
delete from test_info;
insert into test_info values (2010, 'hello, line
suped
seped
"end'
);
向数据表导入数据
load data local infile '/tmp/test.csv' into table test_info fields terminated by ',' optionally enclosed by '"' escaped by '"' lines terminated by 'rn';
增加列
alter table t_icf_day add new_field_id int(5);
alter table t_icf_day add column day_id BIGINT primary key auto_increment;
设主键
alter table userinfo add prmariy key (userId);
删除表
drop table
drop table if exits '%s_T_ICF_HIST_DATE'
删除列
alter table t2 drop column c;
查找不重复的数据
insert into T_ICF_HIST_D select a.* from China_t_icf_hist_d a,(select c_gouki,c_kisyu,count(*) from %s_T_ICF_DAY group by c_gouki,c_kisyu having count(*)>=1) as b where a.c_gouki=b.c_gouki and a.c_kisyu=b.c_kisyu;",
重命名列
alter table t1 change a b integer;
改变列的类型
alter table t1 change b b bigint not null;
alter table infos change list list tinyint not null default '0';
重命名表
alter table t1 rename t2;
多表查询
select c.nom, e.nom from consultant c, affaire a, besoin b, salarie sa, site s, entreprise e
where c.consultant_id=a.consultant_id and a.besoin_id=b.besoin_id and b.salarie_id=sa.salarie_id and sa.site_id=s.site_id and s.entreprise_id=e.entreprise_id
插入符合条件的列
insert into gansu_icf_hist_d select b.* from gansu_t_icf_day a, T_ICF_HIST_D b where a.c_kisyu=b.c_kisyu and a.c_gouki=b.c_gouki;
insert into gansu_day select a.* from t_icf_day a, gansu_gis_convert_result b where a.d_hassei=b.d_hassei and a.c_gouki=b.c_gouki;
查询后,插入表中
insert into gansu_gis_convert_result SELECT * FROM t_gis_convert_result_icf_other where nv_place='GANSU, China';
向表中添加数据
1 insert into employee values (’200301’,’zhangsan’,’m’,’1978/5/8’);
2 insert into employee values (’200302’,’lisi’,’f’,’1973/3/20’);
创建索引
1 create table test1 (test1_id char(4),name char(20), index idx_test1(name(10)));
2 create index idx_employee on employee(name); 用create为name列创建索引
察看索引
1 show index from employee;
2 show index from products;
删除索引
drop index idx_employee on employee;
alter table products drop index idx_products;
查看代码
select * from gansu_day group by c_kisyu and d_hassei and c_gouki having count(*) > 1;
多表查询
insert into yunnan_gis_convert_result SELECT * FROM t_gis_convert_result_icf_AWS where nv_place='YUNNAN, China' union all
SELECT * FROM t_gis_convert_result_icf_AXA_AWU where nv_place='YUNNAN, China' union all SELECT * FROM t_gis_convert_result_icf_other where nv_place='YUNNAN, China';
insert into LIAONING_T_ICF_HIST_D select a.* from China_t_icf_hist_d a,(select c_gouki,c_kisyu,count(*) from LIAONING_T_ICF_DAY group by c_gouki,c_kisyu having count(*)>=1) as b where a.c_gouki=b.c_gouki and a.c_kisyu=b.c_kisyu;
其实直接看mysql的syntax就可以,不过没有这样直观。
下面给出c++链接mysql语句
MYSQL_RES *Querysql(char *sql) {
MYSQL_RES *res;
MYSQL_ROW row;
char *server = "localhost";/*服务器名*/
char *user = "root";/*用户名*/
char *password = ""; /* 此处改成你的密码 */
char *database = "EserviceDB";/*数据库名*/
MYSQL *conn = mysql_init(NULL);
/* Connect to database */
if (!mysql_real_connect(conn, server, user, password, database, 0, NULL, 0)) {
fprintf(stderr, "%sn", mysql_error(conn));
return res;
}
/* send SQL query */
if (mysql_query(conn, sql)) {//sql语句
fprintf(stderr, "%sn", mysql_error(conn));
return res;
}
res = mysql_store_result(conn);//保存查询结果
mysql_close(conn);
return res;
}
这个函数主要用来链接数据库,返回带有数据格式为:MYSQL_RES,主要用于查询操作:
void NoQuery(char *sql) {
MYSQL_RES *res;
MYSQL_ROW row;
char *server = "localhost";/*服务器名*/
char *user = "root";/*用户名*/
char *password = ""; /* 此处改成你的密码 */
char *database = "EserviceDB";/*数据库名*/
MYSQL *conn = mysql_init(NULL);
if (!mysql_real_connect(conn, server, user, password, database, 0, NULL, 0)) {
fprintf(stderr, "%sn", mysql_error(conn));
printf("the connection fail!");
}
if (mysql_query(conn, sql)) {//sql语句
fprintf(stderr, "%sn", mysql_error(conn));
printf("the query fail!");
} else
printf("query insert sql sucess");
mysql_close(conn);
}
该函数主要用来插入,删除,添加功能。
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