编译libsqlite3.so共享库

gcc -g -shared -fPIC -c sqlite3.c
gcc -g -shared -fPIC -o libsqlite3.so sqlite3.o

libsqlite3.so库的使用

应用程序可通过链接生成的libsqlite3.so来实现对数据库的管理(创建数据库、创建表格、插入数据、查询、数据、删除数据等)。下面以test.c为例

/*********************************************************************************
 *      Copyright:  (C) 2017 zoulei
 *                  All rights reserved.
 *
 *       Filename:  insert.c
 *    Description:  This file i
 *
 *        Version:  1.0.0(2017年06月22日)
 *         Author:  zoulei <zoulei121@gmail.com>
 *      ChangeLog:  1, Release initial version on "2017年06月22日 19时31分12秒"
 *
 ********************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include "sqlite3.h"
#define _DEBUG_
int main(int argc, char**argv)
{
     sqlite3 *db=NULL;
     int len;
     int i=0;
     int nrow=0;
     int ncolumn = 0;
     char *zErrMsg =NULL;
     char **azResult=NULL; //二维数组存放结果
     /* 打开数据库 */
     len = sqlite3_open("user",&db);
     if( len )
     {
        /*  fprintf函数格式化输出错误信息到指定的stderr文件流中  */
        fprintf(stderr, "Can't open database: %sn", sqlite3_errmsg(db));//sqlite3_errmsg(db)用以获得数据库打开错误码的英文描述。
        sqlite3_close(db);
        exit(1);
     }
     else printf("You have opened a sqlite3 database named user successfully!n");

     /* 创建表 */
     char *sql = " CREATE TABLE SensorData(
         ID INTEDER PRIMARY KEY,
         SensorID INTEGER,
         siteNum INTEGER,
         Time VARCHAR(12),
         SensorParameter REAL
         );" ;

      sqlite3_exec(db,sql,NULL,NULL,&zErrMsg);
#ifdef _DEBUG_
      printf("%sn",zErrMsg);
      sqlite3_free(zErrMsg);
#endif
      /*插入数据  */
      char*sql1 ="INSERT INTO 'SensorData'VALUES(NULL,1,2,201430506201,13.5);";
      sqlite3_exec(db,sql1,NULL,NULL,&zErrMsg);
      char*sql2 ="INSERT INTO 'SensorData'VALUES(NULL,3,4,201530506302,14.5);";
      sqlite3_exec(db,sql2,NULL,NULL,&zErrMsg);
      char*sql3 ="INSERT INTO 'SensorData'VALUES(NULL,5,6,201630506413,18.6);";
      sqlite3_exec(db,sql3,NULL,NULL,&zErrMsg);

      /* 查询数据 */
      sql="select *from SensorData";
      sqlite3_get_table( db , sql , &azResult , &nrow , &ncolumn , &zErrMsg );
      printf("nrow=%d ncolumn=%dn",nrow,ncolumn);
      printf("the result is:n");
      for(i=0;i<(nrow+1)*ncolumn;i++)
        {
          printf("azResult[%d]=%sn",i,azResult[i]);
        }

     /* 删除某个特定的数据 */
      sql="delete from SensorData where SensorID = 1 ;";
      sqlite3_exec( db , sql , NULL , NULL , &zErrMsg );
#ifdef _DEBUG_
      printf("zErrMsg = %s n", zErrMsg);
      sqlite3_free(zErrMsg);
#endif

      /* 查询删除后的数据 */
      sql = "SELECT * FROM SensorData ";
      sqlite3_get_table( db , sql , &azResult , &nrow , &ncolumn , &zErrMsg );
      printf( "row:%d column=%dn " , nrow , ncolumn );
      printf( "After deleting , the result is : n" );
      for( i=0 ; i<( nrow + 1 ) * ncolumn ; i++ )
      {
            printf( "azResult[%d] = %sn", i , azResult[i] );
      }
      sqlite3_free_table(azResult);
#ifdef _DEBUG_
   printf("zErrMsg = %s n", zErrMsg);
   sqlite3_free(zErrMsg);
#endif

      sqlite3_close(db);
      return 0;

}