1 MYSQL * STDCALL mysql_real_connect(MYSQL *mysql, const char *host,
2 const char *user,
3 const char *passwd,
4 unsigned int port,
5 const char *unix_socket,
6 unsigned int clientflag);
1. 如何连接数据mysql数据库...。 [gxjun@localhost Mysql]$ cat demo.c
1 //connect to mysql
2 #include<stdio.h>
3 #include"mysql.h"
4
5 int main (void)
6 {
7 MYSQL mysql; //need a instance to init
8
9 int t, r; //connect the database
10
11 mysql_init (&mysql);
12
13 if (!mysql_real_connect
14 (&mysql, "localhost", "root", "123", "demo", 0, NULL, 0))
15 {
16 printf ("Error connecting to database:%s\n", mysql_error (&mysql));
17 }
18 else
19 {
20 printf ("Connected MYSQL successfully!\n");
21 }
22 mysql_close (&mysql);
23 return 0;
24 }
25
26
2.关于make文件的内容： [gxjun@localhost Mysql]$ cat demo.mk
1 .SUFFIXES: .o .c
2
3 CC = gcc
4 SRC = demo.c
5 OBJS = $(SRC : .c = .o)
6 EXEC = demo
7
8 .PHONY: start
9
10 start: $(OBJS)
11
12 $(CC) -o $(EXEC) $(OBJS) -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
13
14 $(OBJS): $(SRC)
15
16 $(CC) -g -Wall $(OBJS) -c $(SRC) #-I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
17
18 .PHONY: clean
19
20 clean:
21 rm -f $(OBJS)
22
/* 几点说明，对于MYSQL数据库程序进行编译，无法像编译普通程序那样，而是要制定include路径，库文件路径和链接模块mysqlclient , 在某些系统上，可能还要用-lz选项链接压缩库。 假设MYSQL的头文件在、usr/include/mysql 路径下 ，库文件在/usr/lib/mysql 路径下，则执行如下命令
-I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
*/
3. 进行make编译： make -f demo.mk
二： 数据查询函数
[gxjun@localhost demo1]$ cat query.c
//select.c
1 #include<stdio.h>
2 #include"mysql.h"
3
4 int main (void)
5 {
6
7 MYSQL mysql;
8 MYSQL_RES *res;
9 MYSQL_ROW row;
10 char *query;
11 int flag, t; //connect the database
12
13 mysql_init (&mysql);
14 if (!mysql_real_connect
15 (&mysql, "localhost", "root", "123", "demo", 0, NULL, 0))
16 {
17 printf ("Failed to connect to Mysql! \n");
18 return 0;
19 }
20 else
21 {
22 printf ("Connected MySQL successfully!\n");
23 query = "select * from student";
24 flag = mysql_real_query (&mysql, query, (unsigned int) strlen (query));
25 if (flag)
26 {
27 printf ("query failed ! \n");
28 return 0;
29 }
30 else
31 {
32 printf ("[ %s ] made...\n", query);
33 }
34 res = mysql_store_result (&mysql);
35 while (row = mysql_fetch_row (res))
36 {
37 for (t = 0; t < mysql_num_fields (res); t++)
38 printf ("%s ", row[t]);
39 printf ("\n");
40 }
41 mysql_close (&mysql);
42 return 0;
43 }
44
45 return 0;
46 }
函数关于Mysql查询语句： （1） int STDCALL mysql_query(MYSQL *mysql, const char *q); （2） int STDCALL mysql_real_query(MYSQL *mysql, const char *q, unsigned int length); 关于这两个函数，使用较多的为（2）式 //makefile文件.... [gxjun@localhost demo1]$ cat query.mk
1 .SUFFIXES: .o .c
2 CC = gcc
3 SRC = query.c
4 OBJS = $(SRC: .c = .o)
5 EXEC = Demo
6 CLS = rm
7
8 .PHONY: start
9
10 start: $(OBJS)
11
12 $(CC) -o $(EXEC) $(OBJS) -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
13
14 $(OBJS): $(SRC)
15
16 $(CC) -g -Wall $(OBJS) -c $(SRC) -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
17 .PHONY: clean
18 clean:
19 $(CLS) -f $(OBJS)
关于bash 语言： [gxjun@localhost demo1]$ cat query.sh
indent -gnu query.c
echo "make is running ....!"
make -f query.mk
echo "make is stopping ....! "
使用关于nm 查看想要看的函数 ； [gxjun@localhost demo1]$ nm Demo
08049aac A __bss_start
080485d0 t call_gmon_start
08049aac b completed.1
08049a64 d __CTOR_END__
08049a60 d __CTOR_LIST__
08049984 D __data_start
08049984 W data_start
08048864 t __do_global_ctors_aux
080485f4 t __do_global_dtors_aux
08049988 D __dso_handle
08049a6c d __DTOR_END__
08049a68 d __DTOR_LIST__
08049990 A _DYNAMIC
08049aac A _edata
08048980 r __EH_FRAME_BEGIN__
08049ab0 A _end
08048888 T _fini
08049984 A __fini_array_end
08049984 A __fini_array_start
080488c0 R _fp_hw
08048630 t frame_dummy
08048980 r __FRAME_END__
08049a74 A _GLOBAL_OFFSET_TABLE_
w __gmon_start__
080484e4 T _init
08049984 A __init_array_end
08049984 A __init_array_start
080488c4 R _IO_stdin_used
08049a70 d __JCR_END__
08049a70 d __JCR_LIST__
w _Jv_RegisterClasses
08048830 T __libc_csu_fini
08048800 T __libc_csu_init
U __libc_start_main@@GLIBC_2.0
0804865c T main
U mysql_close
U mysql_fetch_row
U mysql_init
U mysql_num_fields
U mysql_real_connect
U mysql_real_query
U mysql_store_result
0804998c d p.0
U printf@@GLIBC_2.0
080485ac T _start
我们想要查询的表单：
mysql> select * from student
-> ;
+------+-------+
| sno | sname |
+------+-------+
| 1001 | jim |
+------+-------+
1 row in set (0.05 sec)
关于MYSQL函数查询结果: [gxjun@localhost demo1]$ ./Demo
Connected MySQL successfully!
[ select * from student ] made...
1001 jim
---------------------------------------------华丽丽的分割线-----------------------------------------------------
关于数据库的插入和查询以及连接的综合案列：
[gxjun@localhost demo2]$ cat adddata.c
1 #include<stdio.h>
2 #include<string.h>
3 #include<stdlib.h>
4 #include "mysql.h"
5 //#include<fcntl.h>
6
7 int
8 main (void)
9 {
10
11 MYSQL mysql; //var mysql
12 MYSQL_RES *res; //grep_result
13 MYSQL_ROW row; //mysql_row
14 int r; //var_tmp r
15 char *query[4];
16 int flag;
17 //init_mysql
18 mysql_init (&mysql);
19 if (!mysql_real_connect
20 (&mysql, "localhost", "root", "123", "demo", 0, NULL, 0))
21 {
22
23 printf ("can't connect the mysql ! errInfo=[%s]", mysql_error (&mysql));
24
25 }
26 else
27 {
28 printf ("connect the mysql successfully!");
29 query[0] = "insert into student(sno,sname)values(1002,'tom')";
30 query[1] = "insert into student(sno,sname)values(1003,'gongxijun')";
31 query[2] = "insert into student(sno,sname)values(1004,'qinshihuang')";
32 //insert data to mysql
33 for (r = 0; r < 3; r++)
34 {
35 if (mysql_real_query
36 (&mysql, query[r], (unsigned int) strlen (query[r])))
37 {
38 printf ("insert data[%d] is failed !\n", r);
39 return 0;
40 }
41 else
42 {
43 printf ("Insert data[%d] is successfully !\n", r);
44 }
45 }
46 }
47
48 //query part
49 query[3] = "select * from student";
50 flag =
51 mysql_real_query (&mysql, query[3], (unsigned int) strlen (query[3]));
52 if (!flag)
53 {
54 res = mysql_store_result (&mysql);
55 while (row = mysql_fetch_row (res))
56 {
57 for (r = 0; r < mysql_num_fields (res); r++)
58 {
59 printf ("%s ", row[r]);
60 }
61 printf ("\n");
62 }
63 }
64 else
65 {
66 printf ("query failed !\n");
67 return 0;
68
69 }
70 mysql_close (&mysql);
71 return 0;
72 }
73
//关于makefile文件： [gxjun@localhost demo2]$ cat adddata.mk
1 .SUFFIXES: .o .c
2 CC = gcc
3 SRC = adddata.c
4 OBJS = $(SRC: .c = .o)
5 EXEC = Demo
6
7 .PHONY: start
8 start: $(OBJS)
9
10 $(CC) -o $(EXEC) $(OBJS) -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
11
12 $(OBJS): $(SRC)
13
14 $(CC) -g -Wall $(OBJS) -c $(SRC) -I/usr/include/mysql -L/usr/lib/mysql -lmysqlcilent
15
16 .PHONY: clean
17
18 clean:
19 rm -f $(OBJS) core.*
20
21
//关于shell文件 [gxjun@localhost demo2]$ cat adddata.sh
1 #!/bin/bash/
2
3 echo "make is starting ....!"
4 indent -gnu adddata.c
5
6 make -f adddata.mk
7 echo "make is endding ...! "
8
9
显示结果： [gxjun@localhost demo2]$ ./Demo
connect the mysql successfully!Insert data[0] is successfully !
Insert data[1] is successfully !
Insert data[2] is successfully !
1001 jim
1002 tom
1003 gongxijun
1004 qinshihuang
[gxjun@localhost demo2]$ ls 关于数据库的插入和查询以及连接的综合案列： [gxjun@localhost demo2]$ cat adddata.c
1 #include<stdio.h>
2 #include<string.h>
3 #include<stdlib.h>
4 #include "mysql.h"
5 //#include<fcntl.h>
6
7 int
8 main (void)
9 {
10
11 MYSQL mysql; //var mysql
12 MYSQL_RES *res; //grep_result
13 MYSQL_ROW row; //mysql_row
14 int r; //var_tmp r
15 char *query[4];
16 int flag;
17 //init_mysql
18 mysql_init (&mysql);
19 if (!mysql_real_connect
20 (&mysql, "localhost", "root", "123", "demo", 0, NULL, 0))
21 {
22
23 printf ("can't connect the mysql ! errInfo=[%s]", mysql_error (&mysql));
24
25 }
26 else
27 {
28 printf ("connect the mysql successfully!");
29 query[0] = "insert into student(sno,sname)values(1002,'tom')";
30 query[1] = "insert into student(sno,sname)values(1003,'gongxijun')";
31 query[2] = "insert into student(sno,sname)values(1004,'qinshihuang')";
32 //insert data to mysql
33 for (r = 0; r < 3; r++)
34 {
35 if (mysql_real_query
36 (&mysql, query[r], (unsigned int) strlen (query[r])))
37 {
38 printf ("insert data[%d] is failed !\n", r);
39 return 0;
40 }
41 else
42 {
43 printf ("Insert data[%d] is successfully !\n", r);
44 }
45 }
46 }
47
48 //query part
49 query[3] = "select * from student";
50 flag =
51 mysql_real_query (&mysql, query[3], (unsigned int) strlen (query[3]));
52 if (!flag)
53 {
54 res = mysql_store_result (&mysql);
55 while (row = mysql_fetch_row (res))
56 {
57 for (r = 0; r < mysql_num_fields (res); r++)
58 {
59 printf ("%s ", row[r]);
60 }
61 printf ("\n");
62 }
63 }
64 else
65 {
66 printf ("query failed !\n");
67 return 0;
68
69 }
70 mysql_close (&mysql);
71 return 0;
72 }
73
//关于makefile文件： [gxjun@localhost demo2]$ cat adddata.mk
1 .SUFFIXES: .o .c
2 CC = gcc
3 SRC = adddata.c
4 OBJS = $(SRC: .c = .o)
5 EXEC = Demo
6
7 .PHONY: start
8 start: $(OBJS)
9
10 $(CC) -o $(EXEC) $(OBJS) -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
11
12 $(OBJS): $(SRC)
13
14 $(CC) -g -Wall $(OBJS) -c $(SRC) -I/usr/include/mysql -L/usr/lib/mysql -lmysqlcilent
15
16 .PHONY: clean
17
18 clean:
19 rm -f $(OBJS) core.*
//关于shell文件 [gxjun@localhost demo2]$ cat adddata.sh
1 #!/bin/bash/
2
3 echo "make is starting ....!"
4 indent -gnu adddata.c
5
6 make -f adddata.mk
7 echo "make is endding ...! "
8
显示结果：
[gxjun@localhost demo2]$ ./Demo
connect the mysql successfully!Insert data[0] is successfully !
Insert data[1] is successfully !
Insert data[2] is successfully !
1001 jim
1002 tom
1003 gongxijun
1004 qinshihuang
[gxjun@localhost demo2]$ ls
-------------------------------------华丽丽的分割线-----------------------------------------------------------
|++++++++++++++++++++++显示删除和查询功能++++++++++++++++++++++++++++++++++++|
del.c代码：
1 #include<stdio.h>
2 #include<string.h>
3 #include "mysql.h"
4
5 int
6 main (void)
7 {
8
9 MYSQL mysql;
10
11 MYSQL_RES *res;
12
13 MYSQL_ROW row;
14 char *query;
15 int rr, flag;
16 mysql_init (&mysql); //init mysql
17 MYSQL *pts = mysql_real_connect (&mysql, "localhost", "root", "123", "demo", 0, NULL, 0); //to connect the mysql
18 if (pts == NULL)
19 {
20 printf ("connect is failed ! [%s ]\n", mysql_error (&mysql));
21 return 0;
22 }
23 printf ("conected successfully ! \n");
24 //the part of function is to query the data of mysql
25
26 query = "select * from student ";
27
28 flag = mysql_real_query (&mysql, query, (unsigned int) strlen (query));
29 if (flag)
30 {
31 printf ("query the mysql is failed ! [%s ] \n", mysql_error (&mysql));
32 return 0;
33 }
34
35 res = mysql_store_result (&mysql); // return a point of res (var MYSQL_RES *)
36
37 while (row = mysql_fetch_row (res))
38 { //to next row
39
40 for (rr = 0; rr < mysql_num_fields (res); rr++)
41 printf ("[ %s ] ", row[rr]);
42 puts ("");
43 }
44 //the part of del the data of mysql
45 query = "delete from student where sname = 'gongxijun'";
46 flag = mysql_real_query (&mysql, query, (unsigned int) strlen (query));
47 if (flag)
48 {
49 printf ("sorry ,delect the data of mysql is failed !\n [%s ] ",
50 mysql_error (&mysql));
51 return 0;
52 }
53 //query again
54 query = "select * from student ";
55 flag = mysql_real_query (&mysql, query, (unsigned int) strlen (query));
56 if (flag)
57 {
58 printf ("query failed ! the result= [%s ] \n", mysql_error (&mysql));
59 return 0;
60 }
61 res = mysql_store_result (&mysql);
62 while (row = mysql_fetch_row (res))
63 {
64 for (rr = 0; rr < mysql_num_fields (res); rr++)
65 printf ("[%s ]\n", row[rr]);
66 printf ("\n");
67 }
68 mysql_close (&mysql); //close mysql
69 return 0;
70 }
71
关于makefile文件 ： del.mk
1 .SUFFIXES: .o .c
2 CC = gcc
3 SRC = del.c
4 OBJS = $(SRC: .c =.o)
5 EXEC = Demo
6
7 .PHONY: start
8 start: $(OBJS)
9
10 $(CC) -o $(EXEC) $(OBJS) -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
11
12 $(OBJS): $(SRC)
13
14 $(CC) -g -Wall $(OBJS) -c $(SRC) -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
15
16 .PHONY: clean
17 clean:
18 rm -f $(OBJS) core.*
19
20 ~
21 ~
关于bash文件： indent -gnu del.c
make -f del.mk
显示结果：
[gxjun@localhost demo3]$ bash del.sh
bash: /root/.bashrc: 权限不够
make: Circular del.c <- del.c dependency dropped.
gcc -o Demo del.c -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
[gxjun@localhost demo3]$ ./Demo
conected successfully !
[ 1001 ] [ jim ]
[ 1002 ] [ tom ]
[ 1003 ] [ gongxijun ]
[ 1004 ] [ qinshihuang ]
sorry ,delect the data of mysql is failed !
[You have an error in your SQL syntax near '* from student where sname =gongxijun' at line 1 ] [gxjun@localhost demo3]$ vi del.c
[gxjun@localhost demo3]$ bash del.sh
bash: /root/.bashrc: 权限不够
make: Circular del.c <- del.c dependency dropped.
gcc -o Demo del.c -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
[gxjun@localhost demo3]$ ./Demo
conected successfully !
[ 1001 ] [ jim ]
[ 1002 ] [ tom ]
[ 1003 ] [ gongxijun ]
[ 1004 ] [ qinshihuang ]
sorry ,delect the data of mysql is failed !
[Unknown column 'gongxijun' in 'where clause' ] [gxjun@localhost demo3]$
[gxjun@localhost demo3]$
[gxjun@localhost demo3]$ vi del.c
[gxjun@localhost demo3]$ bash del.sh
bash: /root/.bashrc: 权限不够
make: Circular del.c <- del.c dependency dropped.
gcc -o Demo del.c -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient
[gxjun@localhost demo3]$ ./Demo
conected successfully !
[ 1001 ] [ jim ]
[ 1002 ] [ tom ]
[ 1003 ] [ gongxijun ]
[ 1004 ] [ qinshihuang ]
[1001 ]
[jim ]
[1002 ]
[tom ]
[1004 ]
[qinshihuang ]
编程是一种快乐，享受代码带给我的乐趣！！！
