Ghost insert

Hi.

I am trying to do a interface from a web over my database postgresql
whit libpq.

I can't do a simple 'insert' from libpq.

I'm doing this:

sprintf(temp_string,"insert into clientes
values('fff','prueba','123','123','pepe gotera','jjjjjj','jjj')");

res1=PQexec(conn,temp_string);
tuplas=PQresultStatus(res1);
imprime_cab_html(0);

printf("Resultado: %s<br><p>\n",PQresStatus(tuplas));
printf("Temp_string: %s\n",temp_string);

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And the result on my web it's OK:

Resultado: PGRES_COMMAND_OK

Temp_string: insert into clientes
values('fff','prueba','123','123','pepe gotera','jjjjjj','jjj')

But the insert hasn't effect on my database. If from my database i do
'select * from clientes;' the result it's empty.

Where it's the problem?.

Thanks in advanced.

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