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HomeDatabaseMysql TutorialMySQL的一些语法和C API

25)MYSQL_FIELD *mysql_fetch_fields(MYSQL_RES *result)//结果集中所有列信息26)MYSQL_RES *mysql_list_dbs(MYSQL *mysql,const

select ID,name,zi,hao into outfile "zuozhe.txt" fields optionally enclosed by '""' terminated by ','

from gushizuozhe

load data infile "zuozhe.txt" into table gushizuozhe fields optionally enclosed by '\"' terminated by

',' (ID,name,zi,hao);

grant select on *.* to "public@192.168.%" identified by 'public';

revoke select on *.* from "public@192.168.%"
revoke 并不能删除用户,delete from mysql.user where user like "public%"

flush flush_option[,flush_option]

kill thread_id unix/linux下进行
show processlist
select user()

set password for www@localhost=password("www")

set option_setting

写锁、读锁
lock tables gushi write,gushizuozhe write;
unlock tables


MYSQL编程接口
MYSQL C API
1、数据类型
1)my_ulonglong
2)my_bool
3)MYSQL_FIELD_OFFSET
4)MYSQL
5)MYSQL_RES
6)MYSQL_ROW
7)MYSQL_FIELD
{
char *name;
char *table;
char *def;
enum enum_field_types type;//列的数据类型
unsigned int length;//列定义的长度
unsigned int max_length;//数据实际的最大长度
unsigned int flags;//列的属性
}
8)unsigned int decimals//小数位数

2、函数
1)my_bool mysql_change_user(MYSQL *mysql,const char *user,const char *password,const char *db)
2)void mysql_close(MYSQL *mysql)
3)MYSQL *mysql_init(MYSQL *mysql)
4)int mysql_option(MYSQL *mysql,enum mysql_option,const char *arg)指定更精确的连接参数选项
5)int mysql_ping(MYSQL *mysql)//检查连接是否正常
6)MYSQL *mysql_real_connect(MYSQL *mysql,const char *host,const char *user,const char *password,const

char *db,unsiged int port,const char *unix_socket,unsigned int client_flag)
7)int mysql_select_db(MYSQL *mysql,const char *db)//选择数据库db为当前数据库
8)int mysql_query(MYSQL *mysql,const char *query)
9)int mysql_real_query(MYSQL *mysql,const char *query,unsigned int length)
10)char *mysql_info(MYSQL *mysql)//返回最后执行的一次操作的有关信息。
11)MYSQL_RES *mysql_store_result(MYSQL *mysql)//读取一个查询的全部结果。
12)MYSQL_RES *mysql_use_result(MYSQL *mysql)//初始化一个结果集,但是不把结果读到客户端,仍然保留在服务器上
13)void mysql_free_result(MYSQL_RES *result)//释放结果集使用的内存。
14)my_ulonglong mysql_affected_rows(MYSQL *mysql)//返回最后一个update,delete,insert操作影响的记录数。
15)my_ulonglong mysql_num_rows(MYSQL *mysql)//mysql_store_result()返回的结果集中的记录数。
16)MYSQL_ROW_OFFSET mysql_row_seek(MYSQL_RES *result,MYSQL_ROW_OFFSET offset)
17)MYSQL_ROW_OFFSET mysql_row_tell(MYSQL_RES *result)//当前光标位置
18)MYSQL_ROW_OFFSET mysql_data_seek(MYSQL_RES *result,unsigned long long offset)
19)MYSQL_ROW mysql_fetch_row(MYSQL_RES *result)//结果集中的下一条记录
20)unsigned int mysql_fetch_lengths(MYSQL_RES *result)//结果集中当前记录的长度
21)unsigned int mysql_num_fields(MYSQL_RES *result)//结果集中列的数目
22)MYSQL_FIELD_OFFSET mysql_field_seek(MYSQL_RES *result,MYSQL_FIELD_OFFSET offset)
23)MYSQL_FIELD_OFFSET mysql_field_tell(MYSQL_RES *result)//当前光标位置
24)MYSQL_FIELD *mysql_fetch_field(MYSQL_RES *result)//结果集中当前列信息
25)MYSQL_FIELD *mysql_fetch_fields(MYSQL_RES *result)//结果集中所有列信息
26)MYSQL_RES *mysql_list_dbs(MYSQL *mysql,const char *wild)//与wild正则表达式匹配的数据库信息
27)MYSQL_RES *mysql_list_tables(MYSQL *mysql,const char *wild)//与wild正则表达式匹配的表信息
28)MYSQL_RES *mysql_list_fields(MYSQL *mysql,const char * table,const char *wild)//与当前表,,匹配wild正则表达式的所有列名的结果集
29)MYSQL_RES *mysql_list_processes(MYSQL *mysql)
30)char *mysql_stat(MYSQL *mysql)//当前服务器的信息
31)char *mysql_get_server_info(MYSQL *mysql)
32)char *mysql_get_client_info(MYSQL *mysql)
33)char *mysql_get_host_info(MYSQL *mysql)
34)char *mysql_get_proto_info(MYSQL *mysql)
35)unsiged long mysql_thread_id(MYSQL *mysql)
36)int mysql_kill(MYSQL *mysql,unsiged long pid)
37)int mysql_shutdown(MYSQL *mysql)
38)void mysql_debug(char *debug)
39)int mysql_dump_debug_info(char *debug)
40)unsigned int mysql_errno(MYSQL *mysql)
41)char *mysql_error(MYSQL *mysql)

linux

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How to use MySQL functions for data processing and calculationHow to use MySQL functions for data processing and calculationApr 29, 2025 pm 04:21 PM

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How to use MySQL subquery to improve query efficiencyHow to use MySQL subquery to improve query efficiencyApr 29, 2025 pm 04:09 PM

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How to configure the character set and collation rules of MySQLHow to configure the character set and collation rules of MySQLApr 29, 2025 pm 04:06 PM

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