X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=src%2Fpostgresql.c;h=d6dd0ba20e14399e30107aa1ef3f6674825c0ea3;hb=be99a844a40d7037a910d37a894988b807631a6e;hp=f2d7665ff785a09f92ddfb978b9aa3dd4b7bd84c;hpb=883531cd6271cb8e47adf24973893062db0d3d43;p=collectd.git

diff --git a/src/postgresql.c b/src/postgresql.c
index f2d7665f..d6dd0ba2 100644
--- a/src/postgresql.c
+++ b/src/postgresql.c
@@ -1,6 +1,7 @@
 /**
  * collectd - src/postgresql.c
- * Copyright (C) 2008  Sebastian Harl
+ * Copyright (C) 2008, 2009  Sebastian Harl
+ * Copyright (C) 2009        Florian Forster
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the
@@ -15,8 +16,9 @@
  * with this program; if not, write to the Free Software Foundation, Inc.,
  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  *
- * Author:
+ * Authors:
  *   Sebastian Harl <sh at tokkee.org>
+ *   Florian Forster <octo at verplant.org>
  **/
 
 /*
@@ -29,6 +31,7 @@
 #include "configfile.h"
 #include "plugin.h"
 
+#include "utils_db_query.h"
 #include "utils_complain.h"
 
 #include <pg_config_manual.h>
@@ -80,34 +83,27 @@ typedef enum {
 	C_PSQL_PARAM_HOST = 1,
 	C_PSQL_PARAM_DB,
 	C_PSQL_PARAM_USER,
+	C_PSQL_PARAM_INTERVAL,
 } c_psql_param_t;
 
+/* Parameter configuration. Stored as `user data' in the query objects. */
 typedef struct {
-	char *type;
-	char *type_instance;
-	int   ds_type;
-} c_psql_col_t;
-
-typedef struct {
-	char *name;
-	char *query;
-
 	c_psql_param_t *params;
 	int             params_num;
-
-	c_psql_col_t *cols;
-	int           cols_num;
-} c_psql_query_t;
+} c_psql_user_data_t;
 
 typedef struct {
 	PGconn      *conn;
 	c_complain_t conn_complaint;
 
+	int proto_version;
+	int server_version;
+
 	int max_params_num;
 
 	/* user configuration */
-	c_psql_query_t **queries;
-	int              queries_num;
+	udb_query_t    **queries;
+	size_t           queries_num;
 
 	char *host;
 	char *port;
@@ -123,69 +119,22 @@ typedef struct {
 } c_psql_database_t;
 
 static char *def_queries[] = {
-	"user_tables",
-	"io_user_tables"
+	"backends",
+	"transactions",
+	"queries",
+	"query_plans",
+	"table_states",
+	"disk_io",
+	"disk_usage"
 };
 static int def_queries_num = STATIC_ARRAY_SIZE (def_queries);
 
-static c_psql_query_t *queries          = NULL;
-static int             queries_num      = 0;
+static udb_query_t      **queries       = NULL;
+static size_t             queries_num   = 0;
 
 static c_psql_database_t *databases     = NULL;
 static int                databases_num = 0;
 
-static c_psql_query_t *c_psql_query_new (const char *name)
-{
-	c_psql_query_t *query;
-
-	++queries_num;
-	if (NULL == (queries = (c_psql_query_t *)realloc (queries,
-				queries_num * sizeof (*queries)))) {
-		log_err ("Out of memory.");
-		exit (5);
-	}
-	query = queries + queries_num - 1;
-
-	query->name  = sstrdup (name);
-	query->query = NULL;
-
-	query->params     = NULL;
-	query->params_num = 0;
-
-	query->cols     = NULL;
-	query->cols_num = 0;
-	return query;
-} /* c_psql_query_new */
-
-static void c_psql_query_delete (c_psql_query_t *query)
-{
-	int i;
-
-	sfree (query->name);
-	sfree (query->query);
-
-	sfree (query->params);
-	query->params_num = 0;
-
-	for (i = 0; i < query->cols_num; ++i) {
-		sfree (query->cols[i].type);
-		sfree (query->cols[i].type_instance);
-	}
-	sfree (query->cols);
-	query->cols_num = 0;
-	return;
-} /* c_psql_query_delete */
-
-static c_psql_query_t *c_psql_query_get (const char *name)
-{
-	int i;
-
-	for (i = 0; i < queries_num; ++i)
-		if (0 == strcasecmp (name, queries[i].name))
-			return queries + i;
-	return NULL;
-} /* c_psql_query_get */
-
 static c_psql_database_t *c_psql_database_new (const char *name)
 {
 	c_psql_database_t *db;
@@ -201,13 +150,15 @@ static c_psql_database_t *c_psql_database_new (const char *name)
 
 	db->conn = NULL;
 
-	db->conn_complaint.last     = 0;
-	db->conn_complaint.interval = 0;
+	C_COMPLAIN_INIT (&db->conn_complaint);
+
+	db->proto_version = 0;
+	db->server_version = 0;
 
 	db->max_params_num = 0;
 
-	db->queries     = NULL;
-	db->queries_num = 0;
+	db->queries        = NULL;
+	db->queries_num    = 0;
 
 	db->database   = sstrdup (name);
 	db->host       = NULL;
@@ -226,6 +177,7 @@ static c_psql_database_t *c_psql_database_new (const char *name)
 static void c_psql_database_delete (c_psql_database_t *db)
 {
 	PQfinish (db->conn);
+	db->conn = NULL;
 
 	sfree (db->queries);
 	db->queries_num = 0;
@@ -244,62 +196,6 @@ static void c_psql_database_delete (c_psql_database_t *db)
 	return;
 } /* c_psql_database_delete */
 
-static void submit (const c_psql_database_t *db,
-		const char *type, const char *type_instance,
-		value_t *values, size_t values_len)
-{
-	value_list_t vl = VALUE_LIST_INIT;
-
-	vl.values     = values;
-	vl.values_len = values_len;
-	vl.time       = time (NULL);
-
-	if (C_PSQL_IS_UNIX_DOMAIN_SOCKET (db->host)
-			|| (0 == strcmp (db->host, "localhost")))
-		sstrncpy (vl.host, hostname_g, sizeof (vl.host));
-	else
-		sstrncpy (vl.host, db->host, sizeof (vl.host));
-
-	sstrncpy (vl.plugin, "postgresql", sizeof (vl.plugin));
-	sstrncpy (vl.plugin_instance, db->database, sizeof (vl.plugin_instance));
-
-	sstrncpy (vl.type, type, sizeof (vl.type));
-
-	if (NULL != type_instance)
-		sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
-
-	plugin_dispatch_values (&vl);
-	return;
-} /* submit */
-
-static void submit_counter (const c_psql_database_t *db,
-		const char *type, const char *type_instance,
-		const char *value)
-{
-	value_t values[1];
-
-	if ((NULL == value) || ('\0' == *value))
-		return;
-
-	values[0].counter = atoll (value);
-	submit (db, type, type_instance, values, 1);
-	return;
-} /* submit_counter */
-
-static void submit_gauge (const c_psql_database_t *db,
-		const char *type, const char *type_instance,
-		const char *value)
-{
-	value_t values[1];
-
-	if ((NULL == value) || ('\0' == *value))
-		return;
-
-	values[0].gauge = atof (value);
-	submit (db, type, type_instance, values, 1);
-	return;
-} /* submit_gauge */
-
 static int c_psql_check_connection (c_psql_database_t *db)
 {
 	/* "ping" */
@@ -318,32 +214,40 @@ static int c_psql_check_connection (c_psql_database_t *db)
 					db->database, PQerrorMessage (db->conn));
 			return -1;
 		}
+
+		db->proto_version = PQprotocolVersion (db->conn);
+		if (3 > db->proto_version)
+			log_warn ("Protocol version %d does not support parameters.",
+					db->proto_version);
 	}
 
+	db->server_version = PQserverVersion (db->conn);
+
 	c_release (LOG_INFO, &db->conn_complaint,
 			"Successfully reconnected to database %s", PQdb (db->conn));
 	return 0;
 } /* c_psql_check_connection */
 
-static int c_psql_exec_query (c_psql_database_t *db, int idx)
+static PGresult *c_psql_exec_query_noparams (c_psql_database_t *db,
+		udb_query_t *q)
 {
-	c_psql_query_t *query;
-	PGresult       *res;
+	return PQexec (db->conn, udb_query_get_statement (q));
+} /* c_psql_exec_query_noparams */
 
+static PGresult *c_psql_exec_query_params (c_psql_database_t *db,
+		udb_query_t *q, c_psql_user_data_t *data)
+{
 	char *params[db->max_params_num];
+	char  interval[64];
+	int   i;
 
-	int rows, cols;
-	int i;
-
-	if (idx >= db->queries_num)
-		return -1;
+	if ((data == NULL) || (data->params_num == 0))
+		return (c_psql_exec_query_noparams (db, q));
 
-	query = db->queries[idx];
+	assert (db->max_params_num >= data->params_num);
 
-	assert (db->max_params_num >= query->params_num);
-
-	for (i = 0; i < query->params_num; ++i) {
-		switch (query->params[i]) {
+	for (i = 0; i < data->params_num; ++i) {
+		switch (data->params[i]) {
 			case C_PSQL_PARAM_HOST:
 				params[i] = C_PSQL_IS_UNIX_DOMAIN_SOCKET (db->host)
 					? "localhost" : db->host;
@@ -354,96 +258,138 @@ static int c_psql_exec_query (c_psql_database_t *db, int idx)
 			case C_PSQL_PARAM_USER:
 				params[i] = db->user;
 				break;
+			case C_PSQL_PARAM_INTERVAL:
+				ssnprintf (interval, sizeof (interval), "%i", interval_g);
+				params[i] = interval;
+				break;
 			default:
 				assert (0);
 		}
 	}
 
-	res = PQexecParams (db->conn, query->query, query->params_num, NULL,
-			(const char *const *)((0 == query->params_num) ? NULL : params),
+	return PQexecParams (db->conn, udb_query_get_statement (q),
+			data->params_num, NULL,
+			(const char *const *) params,
 			NULL, NULL, /* return text data */ 0);
+} /* c_psql_exec_query_params */
 
-	if (PGRES_TUPLES_OK != PQresultStatus (res)) {
-		log_err ("Failed to execute SQL query: %s",
-				PQerrorMessage (db->conn));
-		log_info ("SQL query was: %s", query->query);
-		PQclear (res);
-		return -1;
-	}
+static int c_psql_exec_query (c_psql_database_t *db, udb_query_t *q)
+{
+	PGresult *res;
 
-	rows = PQntuples (res);
-	if (1 > rows)
-		return 0;
+	c_psql_user_data_t *data;
 
-	cols = PQnfields (res);
-	if (query->cols_num != cols) {
-		log_err ("SQL query returned wrong number of fields "
-				"(expected: %i, got: %i)", query->cols_num, cols);
-		log_info ("SQL query was: %s", query->query);
-		return -1;
-	}
+	const char *host;
 
-	for (i = 0; i < rows; ++i) {
-		int j;
+	char **column_names;
+	char **column_values;
+	int    column_num;
 
-		for (j = 0; j < cols; ++j) {
-			c_psql_col_t col = query->cols[j];
+	int rows_num;
+	int status;
+	int row, col;
 
-			char *value = PQgetvalue (res, i, j);
+	/* The user data may hold parameter information, but may be NULL. */
+	data = udb_query_get_user_data (q);
 
-			if (col.ds_type == DS_TYPE_COUNTER)
-				submit_counter (db, col.type, col.type_instance, value);
-			else if (col.ds_type == DS_TYPE_GAUGE)
-				submit_gauge (db, col.type, col.type_instance, value);
-		}
+	/* Versions up to `3' don't know how to handle parameters. */
+	if (3 <= db->proto_version)
+		res = c_psql_exec_query_params (db, q, data);
+	else if ((NULL == data) || (0 == data->params_num))
+		res = c_psql_exec_query_noparams (db, q);
+	else {
+		log_err ("Connection to database \"%s\" does not support parameters "
+				"(protocol version %d) - cannot execute query \"%s\".",
+				db->database, db->proto_version,
+				udb_query_get_name (q));
+		return -1;
 	}
-	return 0;
-} /* c_psql_exec_query */
-
-static int c_psql_stat_database (c_psql_database_t *db)
-{
-	const char *const query =
-		"SELECT numbackends, xact_commit, xact_rollback "
-			"FROM pg_stat_database "
-			"WHERE datname = $1;";
-
-	PGresult *res;
 
-	int n;
+	column_names = NULL;
+	column_values = NULL;
 
-	res = PQexecParams (db->conn, query, /* number of parameters */ 1,
-			NULL, (const char *const *)&db->database, NULL, NULL,
-			/* return text data */ 0);
+#define BAIL_OUT(status) \
+	sfree (column_names); \
+	sfree (column_values); \
+	PQclear (res); \
+	return status
 
 	if (PGRES_TUPLES_OK != PQresultStatus (res)) {
 		log_err ("Failed to execute SQL query: %s",
 				PQerrorMessage (db->conn));
-		log_info ("SQL query was: %s", query);
-		PQclear (res);
-		return -1;
+		log_info ("SQL query was: %s",
+				udb_query_get_statement (q));
+		BAIL_OUT (-1);
 	}
 
-	n = PQntuples (res);
-	if (1 < n) {
-		log_warn ("pg_stat_database has more than one entry "
-				"for database %s - ignoring additional results.",
-				db->database);
+	rows_num = PQntuples (res);
+	if (1 > rows_num) {
+		BAIL_OUT (0);
 	}
-	else if (1 > n) {
-		log_err ("pg_stat_database has no entry for database %s",
-				db->database);
-		PQclear (res);
-		return -1;
+
+	column_num = PQnfields (res);
+	column_names = (char **) calloc (column_num, sizeof (char *));
+	if (NULL == column_names) {
+		log_err ("calloc failed.");
+		BAIL_OUT (-1);
+	}
+
+	column_values = (char **) calloc (column_num, sizeof (char *));
+	if (NULL == column_values) {
+		log_err ("calloc failed.");
+		BAIL_OUT (-1);
+	}
+	
+	for (col = 0; col < column_num; ++col) {
+		/* Pointers returned by `PQfname' are freed by `PQclear' via
+		 * `BAIL_OUT'. */
+		column_names[col] = PQfname (res, col);
+		if (NULL == column_names[col]) {
+			log_err ("Failed to resolv name of column %i.", col);
+			BAIL_OUT (-1);
+		}
 	}
 
-	submit_gauge (db, "pg_numbackends", NULL,  PQgetvalue (res, 0, 0));
+	if (C_PSQL_IS_UNIX_DOMAIN_SOCKET (db->host)
+			|| (0 == strcmp (db->host, "localhost")))
+		host = hostname_g;
+	else
+		host = db->host;
+
+	status = udb_query_prepare_result (q, host, "postgresql",
+			db->database, column_names, (size_t) column_num);
+	if (0 != status) {
+		log_err ("udb_query_prepare_result failed with status %i.",
+				status);
+		BAIL_OUT (-1);
+	}
+
+	for (row = 0; row < rows_num; ++row) {
+		for (col = 0; col < column_num; ++col) {
+			/* Pointers returned by `PQgetvalue' are freed by `PQclear' via
+			 * `BAIL_OUT'. */
+			column_values[col] = PQgetvalue (res, row, col);
+			if (NULL == column_values[col]) {
+				log_err ("Failed to get value at (row = %i, col = %i).",
+						row, col);
+				break;
+			}
+		}
 
-	submit_counter (db, "pg_xact", "commit",   PQgetvalue (res, 0, 1));
-	submit_counter (db, "pg_xact", "rollback", PQgetvalue (res, 0, 2));
+		/* check for an error */
+		if (col < column_num)
+			continue;
 
-	PQclear (res);
-	return 0;
-} /* c_psql_stat_database */
+		status = udb_query_handle_result (q, column_values);
+		if (status != 0) {
+			log_err ("udb_query_handle_result failed with status %i.",
+					status);
+		}
+	} /* for (row = 0; row < rows_num; ++row) */
+
+	BAIL_OUT (0);
+#undef BAIL_OUT
+} /* c_psql_exec_query */
 
 static int c_psql_read (void)
 {
@@ -460,10 +406,18 @@ static int c_psql_read (void)
 		if (0 != c_psql_check_connection (db))
 			continue;
 
-		c_psql_stat_database (db);
-
 		for (j = 0; j < db->queries_num; ++j)
-			c_psql_exec_query (db, j);
+		{
+			udb_query_t *q;
+
+			q = db->queries[j];
+
+			if ((0 != db->server_version)
+				&& (udb_query_check_version (q, db->server_version) <= 0))
+				continue;
+
+			c_psql_exec_query (db, q);
+		}
 
 		++success;
 	}
@@ -483,21 +437,16 @@ static int c_psql_shutdown (void)
 	plugin_unregister_read ("postgresql");
 	plugin_unregister_shutdown ("postgresql");
 
-	for (i = 0; i < databases_num; ++i) {
-		c_psql_database_t *db = databases + i;
-		c_psql_database_delete (db);
-	}
+	for (i = 0; i < databases_num; ++i)
+		c_psql_database_delete (databases + i);
 
 	sfree (databases);
 	databases_num = 0;
 
-	for (i = 0; i < queries_num; ++i) {
-		c_psql_query_t *query = queries + i;
-		c_psql_query_delete (query);
-	}
-
-	sfree (queries);
+	udb_query_free (queries, queries_num);
+	queries = NULL;
 	queries_num = 0;
+
 	return 0;
 } /* c_psql_shutdown */
 
@@ -508,33 +457,6 @@ static int c_psql_init (void)
 	if ((NULL == databases) || (0 == databases_num))
 		return 0;
 
-	for (i = 0; i < queries_num; ++i) {
-		c_psql_query_t *query = queries + i;
-		int j;
-
-		for (j = 0; j < query->cols_num; ++j) {
-			c_psql_col_t     *col = query->cols + j;
-			const data_set_t *ds;
-
-			ds = plugin_get_ds (col->type);
-			if (NULL == ds) {
-				log_err ("Column: Unknown type \"%s\".", col->type);
-				c_psql_shutdown ();
-				return -1;
-			}
-
-			if (1 != ds->ds_num) {
-				log_err ("Column: Invalid type \"%s\" - types defining "
-						"one data source are supported only (got: %i).",
-						col->type, ds->ds_num);
-				c_psql_shutdown ();
-				return -1;
-			}
-
-			col->ds_type = ds->ds[0].type;
-		}
-	}
-
 	for (i = 0; i < databases_num; ++i) {
 		c_psql_database_t *db = databases + i;
 
@@ -546,6 +468,12 @@ static int c_psql_init (void)
 		char *server_host;
 		int   server_version;
 
+		/* this will happen during reinitialization */
+		if (NULL != db->conn) {
+			c_psql_check_connection (db);
+			continue;
+		}
+
 		status = ssnprintf (buf, buf_len, "dbname = '%s'", db->database);
 		if (0 < status) {
 			buf     += status;
@@ -564,6 +492,8 @@ static int c_psql_init (void)
 		if (0 != c_psql_check_connection (db))
 			continue;
 
+		db->proto_version = PQprotocolVersion (db->conn);
+
 		server_host    = PQhost (db->conn);
 		server_version = PQserverVersion (db->conn);
 		log_info ("Sucessfully connected to database %s (user %s) "
@@ -572,7 +502,11 @@ static int c_psql_init (void)
 				PQdb (db->conn), PQuser (db->conn),
 				C_PSQL_SOCKET3 (server_host, PQport (db->conn)),
 				C_PSQL_SERVER_VERSION3 (server_version),
-				PQprotocolVersion (db->conn), PQbackendPID (db->conn));
+				db->proto_version, PQbackendPID (db->conn));
+
+		if (3 > db->proto_version)
+			log_warn ("Protocol version %d does not support parameters.",
+					db->proto_version);
 	}
 
 	plugin_register_read ("postgresql", c_psql_read);
@@ -580,7 +514,7 @@ static int c_psql_init (void)
 	return 0;
 } /* c_psql_init */
 
-static int config_set (char *name, char **var, const oconfig_item_t *ci)
+static int config_set_s (char *name, char **var, const oconfig_item_t *ci)
 {
 	if ((0 != ci->children_num) || (1 != ci->values_num)
 			|| (OCONFIG_TYPE_STRING != ci->values[0].type)) {
@@ -591,137 +525,63 @@ static int config_set (char *name, char **var, const oconfig_item_t *ci)
 	sfree (*var);
 	*var = sstrdup (ci->values[0].value.string);
 	return 0;
-} /* config_set */
+} /* config_set_s */
 
-static int config_set_param (c_psql_query_t *query, const oconfig_item_t *ci)
+static int config_query_param_add (udb_query_t *q, oconfig_item_t *ci)
 {
-	c_psql_param_t param;
-	char          *param_str;
+	c_psql_user_data_t *data;
+	const char *param_str;
 
-	if ((0 != ci->children_num) || (1 != ci->values_num)
-			|| (OCONFIG_TYPE_STRING != ci->values[0].type)) {
-		log_err ("Param expects a single string argument.");
-		return 1;
+	c_psql_param_t *tmp;
+
+	data = udb_query_get_user_data (q);
+	if (NULL == data) {
+		data = (c_psql_user_data_t *) smalloc (sizeof (*data));
+		if (NULL == data) {
+			log_err ("Out of memory.");
+			return -1;
+		}
+		memset (data, 0, sizeof (*data));
+		data->params = NULL;
+	}
+
+	tmp = (c_psql_param_t *) realloc (data->params,
+			(data->params_num + 1) * sizeof (c_psql_param_t));
+	if (NULL == tmp) {
+		log_err ("Out of memory.");
+		return -1;
 	}
+	data->params = tmp;
 
 	param_str = ci->values[0].value.string;
 	if (0 == strcasecmp (param_str, "hostname"))
-		param = C_PSQL_PARAM_HOST;
+		data->params[data->params_num] = C_PSQL_PARAM_HOST;
 	else if (0 == strcasecmp (param_str, "database"))
-		param = C_PSQL_PARAM_DB;
+		data->params[data->params_num] = C_PSQL_PARAM_DB;
 	else if (0 == strcasecmp (param_str, "username"))
-		param = C_PSQL_PARAM_USER;
+		data->params[data->params_num] = C_PSQL_PARAM_USER;
+	else if (0 == strcasecmp (param_str, "interval"))
+		data->params[data->params_num] = C_PSQL_PARAM_INTERVAL;
 	else {
 		log_err ("Invalid parameter \"%s\".", param_str);
 		return 1;
 	}
 
-	++query->params_num;
-	if (NULL == (query->params = (c_psql_param_t *)realloc (query->params,
-				query->params_num * sizeof (*query->params)))) {
-		log_err ("Out of memory.");
-		exit (5);
-	}
+	data->params_num++;
+	udb_query_set_user_data (q, data);
 
-	query->params[query->params_num - 1] = param;
-	return 0;
-} /* config_set_param */
+	return (0);
+} /* config_query_param_add */
 
-static int config_set_column (c_psql_query_t *query, const oconfig_item_t *ci)
+static int config_query_callback (udb_query_t *q, oconfig_item_t *ci)
 {
-	c_psql_col_t *col;
-
-	int i;
+	if (0 == strcasecmp ("Param", ci->key))
+		return config_query_param_add (q, ci);
 
-	if ((0 != ci->children_num)
-			|| (1 > ci->values_num) || (2 < ci->values_num)) {
-		log_err ("Column expects either one or two arguments.");
-		return 1;
-	}
+	log_err ("Option not allowed within a Query block: `%s'", ci->key);
 
-	for (i = 0; i < ci->values_num; ++i) {
-		if (OCONFIG_TYPE_STRING != ci->values[i].type) {
-			log_err ("Column expects either one or two string arguments.");
-			return 1;
-		}
-	}
-
-	++query->cols_num;
-	if (NULL == (query->cols = (c_psql_col_t *)realloc (query->cols,
-				query->cols_num * sizeof (*query->cols)))) {
-		log_err ("Out of memory.");
-		exit (5);
-	}
-
-	col = query->cols + query->cols_num - 1;
-
-	col->ds_type = -1;
-
-	col->type = sstrdup (ci->values[0].value.string);
-	col->type_instance = (2 == ci->values_num)
-		? sstrdup (ci->values[1].value.string) : NULL;
-	return 0;
-} /* config_set_column */
-
-static int config_set_query (c_psql_database_t *db, const oconfig_item_t *ci)
-{
-	c_psql_query_t *query;
-
-	if ((0 != ci->children_num) || (1 != ci->values_num)
-			|| (OCONFIG_TYPE_STRING != ci->values[0].type)) {
-		log_err ("Query expects a single string argument.");
-		return 1;
-	}
-
-	query = c_psql_query_get (ci->values[0].value.string);
-	if (NULL == query) {
-		log_err ("Query \"%s\" not found - please check your configuration.",
-				ci->values[0].value.string);
-		return 1;
-	}
-
-	++db->queries_num;
-	if (NULL == (db->queries = (c_psql_query_t **)realloc (db->queries,
-				db->queries_num * sizeof (*db->queries)))) {
-		log_err ("Out of memory.");
-		exit (5);
-	}
-
-	if (query->params_num > db->max_params_num)
-		db->max_params_num = query->params_num;
-
-	db->queries[db->queries_num - 1] = query;
-	return 0;
-} /* config_set_query */
-
-static int c_psql_config_query (oconfig_item_t *ci)
-{
-	c_psql_query_t *query;
-
-	int i;
-
-	if ((1 != ci->values_num)
-			|| (OCONFIG_TYPE_STRING != ci->values[0].type)) {
-		log_err ("<Query> expects a single string argument.");
-		return 1;
-	}
-
-	query = c_psql_query_new (ci->values[0].value.string);
-
-	for (i = 0; i < ci->children_num; ++i) {
-		oconfig_item_t *c = ci->children + i;
-
-		if (0 == strcasecmp (c->key, "Query"))
-			config_set ("Query", &query->query, c);
-		else if (0 == strcasecmp (c->key, "Param"))
-			config_set_param (query, c);
-		else if (0 == strcasecmp (c->key, "Column"))
-			config_set_column (query, c);
-		else
-			log_warn ("Ignoring unknown config key \"%s\".", c->key);
-	}
-	return 0;
-} /* c_psql_config_query */
+	return (-1);
+} /* config_query_callback */
 
 static int c_psql_config_database (oconfig_item_t *ci)
 {
@@ -741,41 +601,43 @@ static int c_psql_config_database (oconfig_item_t *ci)
 		oconfig_item_t *c = ci->children + i;
 
 		if (0 == strcasecmp (c->key, "Host"))
-			config_set ("Host", &db->host, c);
+			config_set_s ("Host", &db->host, c);
 		else if (0 == strcasecmp (c->key, "Port"))
-			config_set ("Port", &db->port, c);
+			config_set_s ("Port", &db->port, c);
 		else if (0 == strcasecmp (c->key, "User"))
-			config_set ("User", &db->user, c);
+			config_set_s ("User", &db->user, c);
 		else if (0 == strcasecmp (c->key, "Password"))
-			config_set ("Password", &db->password, c);
+			config_set_s ("Password", &db->password, c);
 		else if (0 == strcasecmp (c->key, "SSLMode"))
-			config_set ("SSLMode", &db->sslmode, c);
+			config_set_s ("SSLMode", &db->sslmode, c);
 		else if (0 == strcasecmp (c->key, "KRBSrvName"))
-			config_set ("KRBSrvName", &db->krbsrvname, c);
+			config_set_s ("KRBSrvName", &db->krbsrvname, c);
 		else if (0 == strcasecmp (c->key, "Service"))
-			config_set ("Service", &db->service, c);
+			config_set_s ("Service", &db->service, c);
 		else if (0 == strcasecmp (c->key, "Query"))
-			config_set_query (db, c);
+			udb_query_pick_from_list (c, queries, queries_num,
+					&db->queries, &db->queries_num);
 		else
 			log_warn ("Ignoring unknown config key \"%s\".", c->key);
 	}
 
-	if (NULL == db->queries) {
-		db->queries = (c_psql_query_t **)malloc (def_queries_num
-				* sizeof (*db->queries));
-
-		for (i = 0; i < def_queries_num; ++i) {
-			db->queries[i] = c_psql_query_get (def_queries[i]);
-			if (NULL == db->queries[i])
-				log_err ("Query \"%s\" not found - "
-						"please check your installation.",
-						def_queries[i]);
-			else
-				++db->queries_num;
-		}
+	/* If no `Query' options were given, add the default queries.. */
+	if (db->queries_num == 0)
+	{
+		for (i = 0; i < def_queries_num; i++)
+			udb_query_pick_from_list_by_name (def_queries[i],
+					queries, queries_num,
+					&db->queries, &db->queries_num);
+	}
+
+	for (i = 0; (size_t)i < db->queries_num; ++i) {
+		c_psql_user_data_t *data;
+		data = udb_query_get_user_data (db->queries[i]);
+		if ((data != NULL) && (data->params_num > db->max_params_num))
+			db->max_params_num = data->params_num;
 	}
 	return 0;
-}
+} /* c_psql_config_database */
 
 static int c_psql_config (oconfig_item_t *ci)
 {
@@ -803,7 +665,9 @@ static int c_psql_config (oconfig_item_t *ci)
 		oconfig_item_t *c = ci->children + i;
 
 		if (0 == strcasecmp (c->key, "Query"))
-			c_psql_config_query (c);
+			udb_query_create (&queries, &queries_num, c,
+					/* callback = */ config_query_callback,
+					/* legacy mode = */ 1);
 		else if (0 == strcasecmp (c->key, "Database"))
 			c_psql_config_database (c);
 		else
@@ -819,4 +683,3 @@ void module_register (void)
 } /* module_register */
 
 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */
-