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| # データベースへの接続 $conn = Pg::connectdb("user=postgres password=postpass dbname=testdb"); |
| $dbname = $conn->db Returns the database name of the connection. $pguser = $conn->user Returns the Postgres user name of the connection. $pguser = $conn->pass Returns the Postgres password of the connection. $pghost = $conn->host Returns the host name of the connection. $pgport = $conn->port Returns the port of the connection. $pgtty = $conn->tty Returns the tty of the connection. $pgoptions = $conn->options Returns the options used in the connection. $status = $conn->status Returns the status of the connection. For comparing the status you may use the following constants: - PGRES_CONNECTION_OK - PGRES_CONNECTION_BAD $errorMessage = $conn->errorMessage Returns the last error message associated with this connection. $fd = $conn->socket Obtain the file descriptor number for the backend connection socket. A result of -1 indicates that no backend connection is currently open. $pid = $conn->backendPID Returns the process-id of the corresponding backend proceess. $conn->trace(debug_port) Messages passed between frontend and backend are echoed to the debug_port file stream. $conn->untrace Disables tracing. $result = $conn->exec($query) Submits a query to the backend. The return value is a pointer to the PGresult structure, which contains the complete query-result returned by the backend. In case of failure, the pointer points to an empty structure. In this, the perl implementation differs from the C-implementation. Using the old style, even the empty structure has to be freed using PQfree. Before using $result you should call resultStatus to ensure, that the query was properly executed. ($table, $pid) = $conn->notifies Checks for asynchronous notifications. This functions differs from the C-counterpart which returns a pointer to a new allocated structure, whereas the perl implementation returns a list. $table is the table which has been listened to and $pid is the process id of the backend. $ret = $conn->sendQuery($string, $query) Submit a query to Postgres without waiting for the result(s). After successfully calling PQsendQuery, call PQgetResult one or more times to obtain the query results. PQsendQuery may not be called again until getResult has returned NULL, indicating that the query is done. $result = $conn->getResult Wait for the next result from a prior PQsendQuery, and return it. NULL is returned when the query is complete and there will be no more results. getResult will block only if a query is active and the necessary response data has not yet been read by PQconsumeInput. $ret = $conn->isBusy Returns TRUE if a query is busy, that is, PQgetResult would block waiting for input. A FALSE return indicates that PQgetResult can be called with assurance of not blocking. $result = $conn->consumeInput If input is available from the backend, consume it. After calling consumeInput, the application may check isBusy and/or notifies to see if their state has changed. $ret = $conn->getline($string, $length) Reads a string up to $length - 1 characters from the backend. getline returns EOF at EOF, 0 if the entire line has been read, and 1 if the buffer is full. If a line consists of the two characters "\." the backend has finished sending the results of the copy command. $ret = $conn->putline($string) Sends a string to the backend. The application must explicitly send the two characters "\." to indicate to the backend that it has finished sending its data. $ret = $conn->getlineAsync($buffer, $bufsize) Non-blocking version of getline. It reads up to $bufsize characters from the backend. getlineAsync returns -1 if the end-of-copy-marker has been recognized, 0 if no data is avilable, and >0 the number of bytes returned. $ret = $conn->putnbytes($buffer, $nbytes) Sends n bytes to the backend. Returns 0 if OK, EOF if not. $ret = $conn->endcopy This function waits until the backend has finished the copy. It should either be issued when the last string has been sent to the backend using putline or when the last string has been received from the backend using getline. endcopy returns 0 on success, 1 on failure. $result = $conn->makeEmptyPGresult($status); Returns a newly allocated, initialized result with given status. |
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