Esempio n. 1
0
File: common.c Progetto: GisKook/Gis
/*
 * SendQuery: send the query string to the backend
 * (and print out results)
 *
 * Note: This is the "front door" way to send a query. That is, use it to
 * send queries actually entered by the user. These queries will be subject to
 * single step mode.
 * To send "back door" queries (generated by slash commands, etc.) in a
 * controlled way, use PSQLexec().
 *
 * Returns true if the query executed successfully, false otherwise.
 */
bool
SendQuery(const char *query)
{
	PGresult   *results;
	PGTransactionStatusType transaction_status;
	double		elapsed_msec = 0;
	bool		OK,
				on_error_rollback_savepoint = false;
	static bool on_error_rollback_warning = false;

	if (!pset.db)
	{
		psql_error("You are currently not connected to a database.\n");
		return false;
	}

	if (pset.singlestep)
	{
		char		buf[3];

		printf(_("***(Single step mode: verify command)*******************************************\n"
				 "%s\n"
				 "***(press return to proceed or enter x and return to cancel)********************\n"),
			   query);
		fflush(stdout);
		if (fgets(buf, sizeof(buf), stdin) != NULL)
			if (buf[0] == 'x')
				return false;
	}
	else if (pset.echo == PSQL_ECHO_QUERIES)
	{
		puts(query);
		fflush(stdout);
	}

	if (pset.logfile)
	{
		fprintf(pset.logfile,
				_("********* QUERY **********\n"
				  "%s\n"
				  "**************************\n\n"), query);
		fflush(pset.logfile);
	}

	SetCancelConn();

	transaction_status = PQtransactionStatus(pset.db);

	if (transaction_status == PQTRANS_IDLE &&
		!pset.autocommit &&
		!command_no_begin(query))
	{
		results = PQexec(pset.db, "BEGIN");
		if (PQresultStatus(results) != PGRES_COMMAND_OK)
		{
			psql_error("%s", PQerrorMessage(pset.db));
			PQclear(results);
			ResetCancelConn();
			return false;
		}
		PQclear(results);
		transaction_status = PQtransactionStatus(pset.db);
	}

	if (transaction_status == PQTRANS_INTRANS &&
		pset.on_error_rollback != PSQL_ERROR_ROLLBACK_OFF &&
		(pset.cur_cmd_interactive ||
		 pset.on_error_rollback == PSQL_ERROR_ROLLBACK_ON))
	{
		if (on_error_rollback_warning == false && pset.sversion < 80000)
		{
			fprintf(stderr, _("The server (version %d.%d) does not support savepoints for ON_ERROR_ROLLBACK.\n"),
					pset.sversion / 10000, (pset.sversion / 100) % 100);
			on_error_rollback_warning = true;
		}
		else
		{
			results = PQexec(pset.db, "SAVEPOINT pg_psql_temporary_savepoint");
			if (PQresultStatus(results) != PGRES_COMMAND_OK)
			{
				psql_error("%s", PQerrorMessage(pset.db));
				PQclear(results);
				ResetCancelConn();
				return false;
			}
			PQclear(results);
			on_error_rollback_savepoint = true;
		}
	}

	if (pset.fetch_count <= 0 || !is_select_command(query))
	{
		/* Default fetch-it-all-and-print mode */
		instr_time	before,
					after;

		if (pset.timing)
			INSTR_TIME_SET_CURRENT(before);

		results = PQexec(pset.db, query);

		/* these operations are included in the timing result: */
		ResetCancelConn();
		OK = (AcceptResult(results) && ProcessCopyResult(results));

		if (pset.timing)
		{
			INSTR_TIME_SET_CURRENT(after);
			INSTR_TIME_SUBTRACT(after, before);
			elapsed_msec = INSTR_TIME_GET_MILLISEC(after);
		}

		/* but printing results isn't: */
		if (OK)
			OK = PrintQueryResults(results);
	}
	else
	{
		/* Fetch-in-segments mode */
		OK = ExecQueryUsingCursor(query, &elapsed_msec);
		ResetCancelConn();
		results = NULL;			/* PQclear(NULL) does nothing */
	}

	/* If we made a temporary savepoint, possibly release/rollback */
	if (on_error_rollback_savepoint)
	{
		const char *svptcmd;

		transaction_status = PQtransactionStatus(pset.db);

		if (transaction_status == PQTRANS_INERROR)
		{
			/* We always rollback on an error */
			svptcmd = "ROLLBACK TO pg_psql_temporary_savepoint";
		}
		else if (transaction_status != PQTRANS_INTRANS)
		{
			/* If they are no longer in a transaction, then do nothing */
			svptcmd = NULL;
		}
		else
		{
			/*
			 * Do nothing if they are messing with savepoints themselves: If
			 * the user did RELEASE or ROLLBACK, our savepoint is gone. If
			 * they issued a SAVEPOINT, releasing ours would remove theirs.
			 */
			if (results &&
				(strcmp(PQcmdStatus(results), "SAVEPOINT") == 0 ||
				 strcmp(PQcmdStatus(results), "RELEASE") == 0 ||
				 strcmp(PQcmdStatus(results), "ROLLBACK") == 0))
				svptcmd = NULL;
			else
				svptcmd = "RELEASE pg_psql_temporary_savepoint";
		}

		if (svptcmd)
		{
			PGresult   *svptres;

			svptres = PQexec(pset.db, svptcmd);
			if (PQresultStatus(svptres) != PGRES_COMMAND_OK)
			{
				psql_error("%s", PQerrorMessage(pset.db));
				PQclear(svptres);

				PQclear(results);
				ResetCancelConn();
				return false;
			}
			PQclear(svptres);
		}
	}

	PQclear(results);

	/* Possible microtiming output */
	if (OK && pset.timing)
		printf(_("Time: %.3f ms\n"), elapsed_msec);

	/* check for events that may occur during query execution */

	if (pset.encoding != PQclientEncoding(pset.db) &&
		PQclientEncoding(pset.db) >= 0)
	{
		/* track effects of SET CLIENT_ENCODING */
		pset.encoding = PQclientEncoding(pset.db);
		pset.popt.topt.encoding = pset.encoding;
		SetVariable(pset.vars, "ENCODING",
					pg_encoding_to_char(pset.encoding));
	}

	PrintNotifications();

	return OK;
}
Esempio n. 2
0
/*
 * SendQuery: send the query string to the backend
 * (and print out results)
 *
 * Note: This is the "front door" way to send a query. That is, use it to
 * send queries actually entered by the user. These queries will be subject to
 * single step mode.
 * To send "back door" queries (generated by slash commands, etc.) in a
 * controlled way, use PSQLexec().
 *
 * Returns true if the query executed successfully, false otherwise.
 */
bool
SendQuery(const char *query)
{
	PGresult   *results;
	PGTransactionStatusType transaction_status;
	double		elapsed_msec = 0;
	bool		OK = false;
	int			i;
	bool		on_error_rollback_savepoint = false;
	static bool on_error_rollback_warning = false;

	if (!pset.db)
	{
		psql_error("You are currently not connected to a database.\n");
		goto sendquery_cleanup;
	}

	if (pset.singlestep)
	{
		char		buf[3];

		fflush(stderr);
		printf(_("***(Single step mode: verify command)*******************************************\n"
				 "%s\n"
				 "***(press return to proceed or enter x and return to cancel)********************\n"),
			   query);
		fflush(stdout);
		if (fgets(buf, sizeof(buf), stdin) != NULL)
			if (buf[0] == 'x')
				goto sendquery_cleanup;
		if (cancel_pressed)
			goto sendquery_cleanup;
	}
	else if (pset.echo == PSQL_ECHO_QUERIES)
	{
		puts(query);
		fflush(stdout);
	}

	if (pset.logfile)
	{
		fprintf(pset.logfile,
				_("********* QUERY **********\n"
				  "%s\n"
				  "**************************\n\n"), query);
		fflush(pset.logfile);
	}

	SetCancelConn();

	transaction_status = PQtransactionStatus(pset.db);

	if (transaction_status == PQTRANS_IDLE &&
		!pset.autocommit &&
		!command_no_begin(query))
	{
		results = PQexec(pset.db, "BEGIN");
		if (PQresultStatus(results) != PGRES_COMMAND_OK)
		{
			psql_error("%s", PQerrorMessage(pset.db));
			ClearOrSaveResult(results);
			ResetCancelConn();
			goto sendquery_cleanup;
		}
		ClearOrSaveResult(results);
		transaction_status = PQtransactionStatus(pset.db);
	}

	if (transaction_status == PQTRANS_INTRANS &&
		pset.on_error_rollback != PSQL_ERROR_ROLLBACK_OFF &&
		(pset.cur_cmd_interactive ||
		 pset.on_error_rollback == PSQL_ERROR_ROLLBACK_ON))
	{
		if (on_error_rollback_warning == false && pset.sversion < 80000)
		{
			char		sverbuf[32];

			psql_error("The server (version %s) does not support savepoints for ON_ERROR_ROLLBACK.\n",
					   formatPGVersionNumber(pset.sversion, false,
											 sverbuf, sizeof(sverbuf)));
			on_error_rollback_warning = true;
		}
		else
		{
			results = PQexec(pset.db, "SAVEPOINT pg_psql_temporary_savepoint");
			if (PQresultStatus(results) != PGRES_COMMAND_OK)
			{
				psql_error("%s", PQerrorMessage(pset.db));
				ClearOrSaveResult(results);
				ResetCancelConn();
				goto sendquery_cleanup;
			}
			ClearOrSaveResult(results);
			on_error_rollback_savepoint = true;
		}
	}

	if (pset.fetch_count <= 0 || pset.gexec_flag ||
		pset.crosstab_flag || !is_select_command(query))
	{
		/* Default fetch-it-all-and-print mode */
		instr_time	before,
					after;

		if (pset.timing)
			INSTR_TIME_SET_CURRENT(before);

		results = PQexec(pset.db, query);

		/* these operations are included in the timing result: */
		ResetCancelConn();
		OK = ProcessResult(&results);

		if (pset.timing)
		{
			INSTR_TIME_SET_CURRENT(after);
			INSTR_TIME_SUBTRACT(after, before);
			elapsed_msec = INSTR_TIME_GET_MILLISEC(after);
		}

		/* but printing results isn't: */
		if (OK && results)
			OK = PrintQueryResults(results);
	}
	else
	{
		/* Fetch-in-segments mode */
		OK = ExecQueryUsingCursor(query, &elapsed_msec);
		ResetCancelConn();
		results = NULL;			/* PQclear(NULL) does nothing */
	}

	if (!OK && pset.echo == PSQL_ECHO_ERRORS)
		psql_error("STATEMENT:  %s\n", query);

	/* If we made a temporary savepoint, possibly release/rollback */
	if (on_error_rollback_savepoint)
	{
		const char *svptcmd = NULL;

		transaction_status = PQtransactionStatus(pset.db);

		switch (transaction_status)
		{
			case PQTRANS_INERROR:
				/* We always rollback on an error */
				svptcmd = "ROLLBACK TO pg_psql_temporary_savepoint";
				break;

			case PQTRANS_IDLE:
				/* If they are no longer in a transaction, then do nothing */
				break;

			case PQTRANS_INTRANS:

				/*
				 * Do nothing if they are messing with savepoints themselves:
				 * If the user did RELEASE or ROLLBACK, our savepoint is gone.
				 * If they issued a SAVEPOINT, releasing ours would remove
				 * theirs.
				 */
				if (results &&
					(strcmp(PQcmdStatus(results), "SAVEPOINT") == 0 ||
					 strcmp(PQcmdStatus(results), "RELEASE") == 0 ||
					 strcmp(PQcmdStatus(results), "ROLLBACK") == 0))
					svptcmd = NULL;
				else
					svptcmd = "RELEASE pg_psql_temporary_savepoint";
				break;

			case PQTRANS_ACTIVE:
			case PQTRANS_UNKNOWN:
			default:
				OK = false;
				/* PQTRANS_UNKNOWN is expected given a broken connection. */
				if (transaction_status != PQTRANS_UNKNOWN || ConnectionUp())
					psql_error("unexpected transaction status (%d)\n",
							   transaction_status);
				break;
		}

		if (svptcmd)
		{
			PGresult   *svptres;

			svptres = PQexec(pset.db, svptcmd);
			if (PQresultStatus(svptres) != PGRES_COMMAND_OK)
			{
				psql_error("%s", PQerrorMessage(pset.db));
				ClearOrSaveResult(svptres);
				OK = false;

				PQclear(results);
				ResetCancelConn();
				goto sendquery_cleanup;
			}
			PQclear(svptres);
		}
	}

	ClearOrSaveResult(results);

	/* Possible microtiming output */
	if (pset.timing)
		printf(_("Time: %.3f ms\n"), elapsed_msec);

	/* check for events that may occur during query execution */

	if (pset.encoding != PQclientEncoding(pset.db) &&
		PQclientEncoding(pset.db) >= 0)
	{
		/* track effects of SET CLIENT_ENCODING */
		pset.encoding = PQclientEncoding(pset.db);
		pset.popt.topt.encoding = pset.encoding;
		SetVariable(pset.vars, "ENCODING",
					pg_encoding_to_char(pset.encoding));
	}

	PrintNotifications();

	/* perform cleanup that should occur after any attempted query */

sendquery_cleanup:

	/* reset \g's output-to-filename trigger */
	if (pset.gfname)
	{
		free(pset.gfname);
		pset.gfname = NULL;
	}

	/* reset \gset trigger */
	if (pset.gset_prefix)
	{
		free(pset.gset_prefix);
		pset.gset_prefix = NULL;
	}

	/* reset \gexec trigger */
	pset.gexec_flag = false;

	/* reset \crosstabview trigger */
	pset.crosstab_flag = false;
	for (i = 0; i < lengthof(pset.ctv_args); i++)
	{
		pg_free(pset.ctv_args[i]);
		pset.ctv_args[i] = NULL;
	}

	return OK;
}