mysql c语言接口。个人封装

个人封装的一些数据库的c语言接口

#include <stdio.h>#include <stdlib.h>#include <stdio.h>#include "mysql.h"  //我的机器上该文件在/usr/include/mysql下/***********************************************************//*一下操作的表。表名为 mytable*//************************************************************/#define SELECT_QUERY "select * from mytable where name like '%s'"//#define ALL_QUERY "select * from mytable;"MYSQL mysql, *sock; //定义数据连接句柄/*******************************************函数名:    service_sql_init功能:     服务器数据库初始化*********************************************/int service_sql_init(void){    mysql_init(&mysql);    /* 连接上数据库 *///  if(!(sock = mysql_real_connect(&mysql, "localhost", "root", "my-name-is?lza1205", "rt5350_user_list", 0, NULL, 0))){    if(!(sock = mysql_real_connect(&mysql, "localhost", "root", "123456", "agent_user_list", 0, NULL, 0))){        fprintf(stderr, "Couldn't connect to engine!\n%s\n\n", mysql_error(&mysql));        perror("");        exit(1);    }    app_printf("mysql init is ok \r\n");    return 0;}/*******************************************函数名:    service_sql_select功能:     根据name 从服务器中找出passwd*********************************************/int service_sql_select(char *name, char *passwd){    MYSQL_RES   *res;   //查询结果集//  MYSQL_FIELD *fd;    //包含字段信息    MYSQL_ROW   row;    //存放一行查询结果的字符串数组    char qbuf[160];     //存放查询 sql 语句字符串    sprintf(qbuf, SELECT_QUERY, name);    printf("qbuf is %s\n", qbuf);    /* 查询数据库 */    if(mysql_query(sock, qbuf)){        fprintf(stderr, "Query failed (%s)\n", mysql_error(sock));        return -1;    }    if(!(res = mysql_store_result(sock))){        fprintf(stderr, "Couldn't get result from %s\n", mysql_error(sock));        return -1;    }    printf("number of fields returned : %d\n", mysql_num_fields(res));    while((row = mysql_fetch_row(res))){        printf("Ther name #%s 's passwd is: %s\n", (((row[0]==NULL)&&(!strlen(row[0]))) ? "NULL" : row[0]),                                                    (((row[1]==NULL)&&(!strlen(row[1]))) ? "NULL" : row[1]));         puts( "query ok !\n" ) ;         strcpy(passwd, (((row[1]==NULL)&&(!strlen(row[1]))) ? "NULL" : row[1]));        mysql_free_result(res);        return 0;    }    mysql_free_result(res);    return -1;//    mysql_close(sock);}/* 释放结果集 */void __mysql_free_result(void){    MYSQL_RES   *res;   //查询结果集    do    {      if (!(res= mysql_store_result(sock)))      {            return;      }      mysql_free_result(res);    } while (!mysql_next_result(sock));}#define UPDATE_STRING_QUERY "update mytable set %s=\'%s\' where name=\'%s\'"#define UPDATE_INT_QUERY "update mytable set %s=%d where name=\'%s\'"/* 根据名字修改数据库中的某项 */int server_sql_update_string(char *name, char *key, char *val){    char qbuf[160];     //存放查询 sql 语句字符串    sprintf(qbuf, UPDATE_STRING_QUERY, key, val, name);    printf("qbuf is %s\n", qbuf);    /* 查询数据库 */    if(mysql_query(sock, qbuf)){        fprintf(stderr, "Query failed (%s)\n", mysql_error(sock));        return -1;    }    return 0;}int server_sql_update_int(char *name, char *key, unsigned int val){    char qbuf[160];     //存放查询 sql 语句字符串    sprintf(qbuf, UPDATE_INT_QUERY, key, val, name);    printf("qbuf is %s\n", qbuf);    /* 查询数据库 */    if(mysql_query(sock, qbuf)){        fprintf(stderr, "Query failed (%s)\n", mysql_error(sock));        return -1;    }    return 0;}/*    下面的函数可以指定某个表格*/#define UPDATE_TABLE_STRING_QUERY "update %s set %s=\'%s\' where code=\'%s\'"#define UPDATE_TABLE_INT_QUERY "update %s set %s=%d where code=\'%s\'"/*    table :表名    name: 索引    key:    修改的项    val:    修改值*//* 根据索引修改数据库中的某项 */int sql_table_update_string(char *table, char *name, char *key, char *val){    char qbuf[160];     //存放查询 sql 语句字符串    sprintf(qbuf, UPDATE_TABLE_STRING_QUERY, table, key, val, name);    printf("qbuf is %s\n", qbuf);    /* 查询数据库 */    if(mysql_query(sock, qbuf)){        fprintf(stderr, "Query failed (%s)\n", mysql_error(sock));        return -1;    }    return 0;}int sql_table_update_int(char *table, char *name, char *key, unsigned int val){    char qbuf[160];     //存放查询 sql 语句字符串    sprintf(qbuf, UPDATE_TABLE_INT_QUERY, table, key, val, name);    printf("qbuf is %s\n", qbuf);    /* 查询数据库 */    if(mysql_query(sock, qbuf)){        fprintf(stderr, "Query failed (%s)\n", mysql_error(sock));        return -1;    }    return 0;}/* 查询数据库中是否有这个元素 */#define SELECT_STRING_QUERY "select * from %s where %s like \'%s\'"int sql_table_select_string(char *table, char *key, char *val){    char qbuf[160];     //存放查询 sql 语句字符串    MYSQL_RES   *res;   //查询结果集//  MYSQL_FIELD *fd;    //包含字段信息    MYSQL_ROW   row;    //存放一行查询结果的字符串数组    sprintf(qbuf, SELECT_STRING_QUERY, table, key, val);    printf("qbuf is %s\n", qbuf);    /* 查询数据库 */    if(mysql_query(sock, qbuf)){        fprintf(stderr, "Query failed (%s)\n", mysql_error(sock));        return -1;    }    if(!(res = mysql_store_result(sock))){        fprintf(stderr, "Couldn't get result from %s\n", mysql_error(sock));        return -1;    }    printf("number of fields returned : %d\n", mysql_num_fields(res));    while((row = mysql_fetch_row(res))){        mysql_free_result(res);        return 0;    }    mysql_free_result(res);    return -1;}/* 往数据库中插入元素 */#define INSERT_STRING_QUERY "insert into %s (%s) values (\'%s\')"int sql_table_insert(char *table, char *key, char *val){    char qbuf[160];     //存放查询 sql 语句字符串    sprintf(qbuf, INSERT_STRING_QUERY, table, key, val);    printf("qbuf is %s\n", qbuf);    /* 查询数据库 */    if(mysql_query(sock, qbuf)){        fprintf(stderr, "Query failed (%s)\n", mysql_error(sock));        return -1;    }    return 0;}