linux c開(kāi)發(fā)postgresQL的問(wèn)題

xubigtree

如何用linux c實(shí)現(xiàn)在postgresQL的數(shù)據(jù)庫(kù)中插入一條語(yǔ)句啊？求代碼實(shí)現(xiàn)。小弟謝了

osdba

示例代碼：

1. #include <stdio.h>
   
2. #include <stdlib.h>
   
3. #include <libpq-fe.h>
   
4. 
   
5. 
   
6. int main(int argc, char * argv[])
   
7. {
   
8.     PGconn *conn;
   
9.     PGresult * dataset;
   
10.     ConnStatusType pgstatus;
    
11.     char connstr[1024];
    
12.     char szSQL[2048];
    
13.     char * paramValues = NULL;
    
14.     int nParams = 0;
    
15.    
    
16.    
    
17.     sprintf(connstr,
    
18.             "hostaddr=%s dbname=%s port=%d user=%s password=%s",
    
19.             "127.0.0.1", "osdba", 5432, "osdba", "osdba");
    
20.     conn = PQconnectdb(connstr);
    
21.     pgstatus = PQstatus(conn);
    
22.     if (pgstatus == CONNECTION_OK)
    
23.     {
    
24.         printf("Connect database success!\n");
    
25.     }
    
26.     else
    
27.     {
    
28.         printf("Connect database fail:%s\n",PQerrorMessage(conn));
    
29.         return;
    
30.     }
    
31.    
    
32.     sprintf(szSQL, "insert into test values(1,'aaaaaa')");
    
33.     dataset = PQexecParams(conn,
    
34.                            szSQL,
    
35.                            nParams,     /* 參數(shù)個(gè)數(shù) */
    
36.                            NULL,        /* 讓后端推出參數(shù)類(lèi)型 */
    
37.                            (const char * const*)paramValues,
    
38.                            NULL,        /* 因?yàn)槭俏谋�，所以必須要參�?shù)長(zhǎng)度 */
    
39.                            NULL,        /* 缺省是全部文本參數(shù) */
    
40.                            0);          /* 是否是二進(jìn)制結(jié)果 */
    
41. 
    
42.     if(  (PQresultStatus(dataset) == PGRES_COMMAND_OK ) ||(PQresultStatus(dataset) == PGRES_TUPLES_OK))
    
43.     {
    
44.         printf("Successfully execute SQL : %s\n",szSQL);
    
45.     }
    
46.     else
    
47.     {
    
48.         printf("%s\n",PQerrorMessage(conn));
    
49.     }
    
50.    
    
51.     /* 關(guān)閉數(shù)據(jù)庫(kù)連接并清理 */
    
52.     PQfinish(conn);
    
53.     return 0;
    
54. }

復(fù)制代碼

編譯方法：
gcc -I `pg_config --includedir` -L `pg_config --libdir` pgtest.c -o pgtest -l pq

見(jiàn)下面的演示：
osdba@osdba-work:~/src/ctest$ gcc -I `pg_config --includedir` -L `pg_config --libdir` pgtest.c -o pgtest -l pq
osdba@osdba-work:~/src/ctest$ ./pgtest
./pgtest: error while loading shared libraries: libpq.so.5: cannot open shared object file: No such file or directory
osdba@osdba-work:~/src/ctest$ export LD_LIBRARY_PATH=/usr/local/pgsql9.2.1/lib
osdba@osdba-work:~/src/ctest$ ./pgtest
Connect database fail:could not connect to server: Connection refused
        Is the server running on host "127.0.0.1" and accepting
        TCP/IP connections on port 5432?

osdba@osdba-work:~/src/ctest$ pgstart
server starting
osdba@osdba-work:~/src/ctest$ LOG:  database system was shut down at 2012-10-16 18:21:53 CST
LOG:  database system is ready to accept connections
LOG:  autovacuum launcher started

osdba@osdba-work:~/src/ctest$
osdba@osdba-work:~/src/ctest$ ./pgtest
Connect database success!
ERROR:  relation "test" does not exist at character 13
STATEMENT:  insert into test values(1,'aaaaaa')
ERROR:  relation "test" does not exist
LINE 1: insert into test values(1,'aaaaaa')
                    ^

osdba@osdba-work:~/src/ctest$ psql
psql (9.2.1)
Type "help" for help.

osdba=# create table test(id int, name text);
CREATE TABLE
osdba=# \q
osdba@osdba-work:~/src/ctest$ ./pgtest
Connect database success!
Successfully execute SQL : insert into test values(1,'aaaaaa')
osdba@osdba-work:~/src/ctest$ psql
psql (9.2.1)
Type "help" for help.

osdba=# select * from test;
id |  name  
----+--------
  1 | aaaaaa
(1 row)

osdba=#

xubigtree

我再問(wèn)一個(gè)問(wèn)題  假如我insert進(jìn)去的數(shù)字要求用參數(shù)num = 1，str = “aaaaaaaaaaaaaaa”表示 ，拿你的例子 sprintf(szSQL, "insert into test values(1,'aaaaaa')");就是怎么插進(jìn)去啊？
謝謝你了啊