MongoDB学习笔记【3】-- MongoDB C驱动使用
MongoDB官方手册：http://docs.mongodb.org/ecosystem/drivers/c/
下载mongodb C driver
[root@slayer ~]# git clone git://github.com/mongodb/mongo-c-driver.git
编译，安装
#cd mongo-c-driver #make && make install
从官方手册找个demo mongo_c.c
#include <stdio.h> #include <mongo.h> int main() { mongo conn[1]; int status = mongo_client( conn, "127.0.0.1", 27017 ); if( status != MONGO_OK ) { switch ( conn->err ) { case MONGO_CONN_NO_SOCKET: printf( "no socket\n" ); return 1; case MONGO_CONN_FAIL: printf( "connection failed\n" ); return 1; case MONGO_CONN_NOT_MASTER: printf( "not master\n" ); return 1; } } printf( "connection done\n"); mongo_destroy( conn ); return 0; }
编译，运行
[root@slayer mongo-c-driver]# gcc -lmongoc --std=c99 mongo_c.c -o mongo_c [root@slayer mongo-c-driver]# ./mongo_c ./mongo_c: error while loading shared libraries: libmongoc.so.0.7: cannot open shar ed object file: No such file or directory
找不到动态库，找找libmongoc.so.0.7在哪
[root@slayer mongo-c-driver]# find / -name libmongoc.so.0.7 /usr/local/lib/libmongoc.so.0.7
看看ld路径
[root@slayer mongo-c-driver]# cat /etc/ld.so.conf include ld.so.conf.d/*.conf [root@slayer mongo-c-driver]# cat /etc/ld.so.conf.d/* /usr/lib64/mysql /usr/lib/xulrunner-2 /usr/lib64/xulrunner-2
果然没有/usr/local/lib，把它加上试试
[root@slayer mongo-c-driver]# echo /usr/local/lib/ > /etc/ld.so.conf.d/mongoc.conf [root@slayer mongo-c-driver]# ldconfig [root@slayer mongo-c-driver]# !gcc gcc -lmongoc --std=c99 mongo_c.c -o mongo_c [root@slayer mongo-c-driver]# ./mongo_c connection done [root@slayer mongo-c-driver]#
连接成功
简单插入和查询 mongo_c_wr.c
#include <stdlib.h> #include <stdio.h> #include <mongo.h> static void tutorial_insert_batch( mongo *conn ) { bson *p, **ps; char *names[4]; int ages[] = { 29, 24, 24, 32 }; int i, n = 4; names[0] = "Eliot"; names[1] = "Mike"; names[2] = "Mathias"; names[3] = "Richard"; ps = ( bson ** )malloc( sizeof( bson * ) * n); for ( i = 0; i < n; i++ ) { p = ( bson * )malloc( sizeof( bson ) ); bson_init( p ); bson_append_new_oid( p, "_id" ); bson_append_string( p, "name", names[i] ); bson_append_int( p, "age", ages[i] ); bson_finish( p ); ps[i] = p; } mongo_insert_batch( conn, "mydb.fc", ps, n, NULL, 0 ); for ( i = 0; i < n; i++ ) { bson_destroy( ps[i] ); free( ps[i] ); } } /* * === FUNCTION ====================================================================== * Name: main * Description: * ===================================================================================== */ int main ( int argc, char *argv[] ) { mongo conn[1]; int status = mongo_client( conn, "127.0.0.1", 27017 ); if( status != MONGO_OK ) { switch ( conn->err ) { case MONGO_CONN_NO_SOCKET: printf( "no socket\n" ); return 1; case MONGO_CONN_FAIL: printf( "connection failed\n" ); return 1; case MONGO_CONN_NOT_MASTER: printf( "not master\n" ); return 1; } } printf( "connection done\n" ); /* make bson object */ bson *b = (bson*) malloc(sizeof(bson)); bson_init( b ); bson_append_string( b, "name", "Joe" ); bson_append_int( b, "age", 33); bson_finish( b ); bson_print(b); /* insert bson object */ mongo_insert( conn, "mydb.fc", b, NULL); /* destroy Joe */ bson_destroy( b ); free(b); /* batch insert */ tutorial_insert_batch(conn); /* query */ bson query[1]; mongo_cursor cursor[1]; mongo_cursor_init( cursor, conn, "mydb.fc" ); /* query from database */ while (mongo_cursor_next(cursor) == MONGO_OK) bson_print(&cursor->current); mongo_cursor_destroy(cursor); mongo_destroy( conn ); return EXIT_SUCCESS; } /* ---------- end of function main ---------- */
编译运行
[root@slayer mongo-c-driver]# gcc --std=c99 -lmongoc -lbson mongo_c_wr.c -o mcwr mongo_c_wr.c: In function 'tutorial_insert_batch': mongo_c_wr.c:24: warning: passing argument 3 of 'mongo_insert_batch' from incompatible pointer type [root@postgresql mongo-c-driver]# ./mcwr connection done name : 2 Joe age : 16 33 _id : 7 50c99a05c0ac94782d63d5a1 name : 2 Joe age : 16 33 _id : 7 50c99a05c8730a6b00000000 name : 2 Eliot age : 16 29 _id : 7 50c99a05c8730a6b00000001 name : 2 Mike age : 16 24 _id : 7 50c99a05c8730a6b00000002 name : 2 Mathias age : 16 24 _id : 7 50c99a05c8730a6b00000003 name : 2 Richard age : 16 32
