Question

In Oracle OCI and OCCI there are API facilities to perform array inserts where you build up an array of values in the client and send this array along with a prepared statement to the server to insert thousands of entries into a table in a single shot resulting in huge performance improvements in some scenarios. Is there anything similar in PostgreSQL ?

I am using the stock PostgreSQL C API.

Some pseudo code to illustrate what i have in mind:

stmt = con->prepare("INSERT INTO mytable VALUES ($1, $2, $3)");
pg_c_api_array arr(stmt);
for triplet(a, b, c) in mylongarray:
    pg_c_api_variant var = arr.add();
    var.bind(1, a);
    var.bind(2, b);
    var.bind(3, c);
stmt->bindarray(arr);
stmt->exec()

Answer 1

PostgreSQL has similar functionality – statement COPY and COPY API – it is very fast

libpq documentation

char *data = "10\t20\40\n20\t30\t40";

pres = PQexec(pconn, "COPY mytable FROM stdin");

/* can be call repeatedly */ 
copy_result = PQputCopyData(pconn, data, sizeof(data));
if (copy_result != 1)
{
        fprintf(stderr, "Copy to target table failed: %s\n",
                                        PQerrorMessage(pconn));
        EXIT;
}

if (PQputCopyEnd(pconn, NULL) == -1)
{
         fprintf(stderr, "Copy to target table failed: %s\n",
                                            PQerrorMessage(pconn));
                            EXIT;
}

pres = PQgetResult(pconn);
if (PQresultStatus(pres) != PGRES_COMMAND_OK)
{
       fprintf(stderr, "Copy to target table failed:%s\n",
                                            PQerrorMessage(pconn));
           EXIT;
}

PQclear(pres);