Merge commit 'octo/st/netapp' into st/netapp
[collectd.git] / src / postgresql.c
index faad16c..d6dd0ba 100644 (file)
@@ -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>
@@ -80,39 +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;
-
-       int min_pg_version;
-       int max_pg_version;
-} 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;
@@ -138,70 +129,12 @@ static char *def_queries[] = {
 };
 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;
-
-       query->min_pg_version = 0;
-       query->max_pg_version = INT_MAX;
-       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 server_version)
-{
-       int i;
-
-       for (i = 0; i < queries_num; ++i)
-               if (0 == strcasecmp (name, queries[i].name)
-                               && ((-1 == server_version)
-                                       || ((queries[i].min_pg_version <= server_version)
-                                               && (server_version <= queries[i].max_pg_version))))
-                       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;
@@ -217,15 +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;
@@ -263,62 +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" */
@@ -344,21 +221,33 @@ static int c_psql_check_connection (c_psql_database_t *db)
                                        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 PGresult *c_psql_exec_query_noparams (c_psql_database_t *db,
+               udb_query_t *q)
+{
+       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,
-               c_psql_query_t *query)
+               udb_query_t *q, c_psql_user_data_t *data)
 {
        char *params[db->max_params_num];
+       char  interval[64];
        int   i;
 
-       assert (db->max_params_num >= query->params_num);
+       if ((data == NULL) || (data->params_num == 0))
+               return (c_psql_exec_query_noparams (db, q));
+
+       assert (db->max_params_num >= data->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;
@@ -369,85 +258,137 @@ static PGresult *c_psql_exec_query_params (c_psql_database_t *db,
                        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);
                }
        }
 
-       return 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 */
 
-static PGresult *c_psql_exec_query_noparams (c_psql_database_t *db,
-               c_psql_query_t *query)
+static int c_psql_exec_query (c_psql_database_t *db, udb_query_t *q)
 {
-       return PQexec (db->conn, query->query);
-} /* c_psql_exec_query_noparams */
+       PGresult *res;
 
-static int c_psql_exec_query (c_psql_database_t *db, int idx)
-{
-       c_psql_query_t *query;
-       PGresult       *res;
+       c_psql_user_data_t *data;
 
-       int rows, cols;
-       int i;
+       const char *host;
 
-       if (idx >= db->queries_num)
-               return -1;
+       char **column_names;
+       char **column_values;
+       int    column_num;
 
-       query = db->queries[idx];
+       int rows_num;
+       int status;
+       int row, col;
 
+       /* The user data may hold parameter information, but may be NULL. */
+       data = udb_query_get_user_data (q);
+
+       /* Versions up to `3' don't know how to handle parameters. */
        if (3 <= db->proto_version)
-               res = c_psql_exec_query_params (db, query);
-       else if (0 == query->params_num)
-               res = c_psql_exec_query_noparams (db, query);
+               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, query->name);
+                               db->database, db->proto_version,
+                               udb_query_get_name (q));
                return -1;
        }
 
+       column_names = NULL;
+       column_values = NULL;
+
+#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->query);
-               PQclear (res);
-               return -1;
+               log_info ("SQL query was: %s",
+                               udb_query_get_statement (q));
+               BAIL_OUT (-1);
        }
 
-       rows = PQntuples (res);
-       if (1 > rows) {
-               PQclear (res);
-               return 0;
+       rows_num = PQntuples (res);
+       if (1 > rows_num) {
+               BAIL_OUT (0);
        }
 
-       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);
-               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);
        }
 
-       for (i = 0; i < rows; ++i) {
-               int j;
+       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);
+               }
+       }
 
-               for (j = 0; j < cols; ++j) {
-                       c_psql_col_t col = query->cols[j];
+       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;
+                       }
+               }
 
-                       char *value = PQgetvalue (res, i, j);
+               /* check for an error */
+               if (col < column_num)
+                       continue;
 
-                       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);
+               status = udb_query_handle_result (q, column_values);
+               if (status != 0) {
+                       log_err ("udb_query_handle_result failed with status %i.",
+                                       status);
                }
-       }
-       PQclear (res);
-       return 0;
+       } /* for (row = 0; row < rows_num; ++row) */
+
+       BAIL_OUT (0);
+#undef BAIL_OUT
 } /* c_psql_exec_query */
 
 static int c_psql_read (void)
@@ -466,7 +407,17 @@ static int c_psql_read (void)
                        continue;
 
                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;
        }
@@ -486,21 +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 */
 
@@ -511,33 +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;
 
@@ -549,8 +468,6 @@ static int c_psql_init (void)
                char *server_host;
                int   server_version;
 
-               int j;
-
                /* this will happen during reinitialization */
                if (NULL != db->conn) {
                        c_psql_check_connection (db);
@@ -590,33 +507,6 @@ static int c_psql_init (void)
                if (3 > db->proto_version)
                        log_warn ("Protocol version %d does not support parameters.",
                                        db->proto_version);
-
-               /* Now that we know the PostgreSQL server version, we can get the
-                * right version of each query definition. */
-               for (j = 0; j < db->queries_num; ++j) {
-                       c_psql_query_t *tmp;
-
-                       tmp = c_psql_query_get (db->queries[j]->name, server_version);
-
-                       if (tmp == db->queries[j])
-                               continue;
-
-                       if (NULL == tmp) {
-                               log_err ("Query \"%s\" not found for server version %i - "
-                                               "please check your configuration.",
-                                               db->queries[j]->name, server_version);
-
-                               if (db->queries_num - j - 1 > 0)
-                                       memmove (db->queries + j, db->queries + j + 1,
-                                                       (db->queries_num - j - 1) * sizeof (*db->queries));
-
-                               --db->queries_num;
-                               --j;
-                               continue;
-                       }
-
-                       db->queries[j] = tmp;
-               }
        }
 
        plugin_register_read ("postgresql", c_psql_read);
@@ -637,185 +527,61 @@ static int config_set_s (char *name, char **var, const oconfig_item_t *ci)
        return 0;
 } /* config_set_s */
 
-static int config_set_i (char *name, int *var, const oconfig_item_t *ci)
+static int config_query_param_add (udb_query_t *q, oconfig_item_t *ci)
 {
-       if ((0 != ci->children_num) || (1 != ci->values_num)
-                       || (OCONFIG_TYPE_NUMBER != ci->values[0].type)) {
-               log_err ("%s expects a single number argument.", name);
-               return 1;
-       }
+       c_psql_user_data_t *data;
+       const char *param_str;
 
-       *var = (int)ci->values[0].value.number;
-       return 0;
-} /* config_set_i */
+       c_psql_param_t *tmp;
 
-static int config_set_param (c_psql_query_t *query, const oconfig_item_t *ci)
-{
-       c_psql_param_t param;
-       char          *param_str;
+       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;
+       }
 
-       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;
+       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);
-       }
-
-       query->params[query->params_num - 1] = param;
-       return 0;
-} /* config_set_param */
-
-static int config_set_column (c_psql_query_t *query, const oconfig_item_t *ci)
-{
-       c_psql_col_t *col;
-
-       int i;
-
-       if ((0 != ci->children_num)
-                       || (1 > ci->values_num) || (2 < ci->values_num)) {
-               log_err ("Column expects either one or two arguments.");
-               return 1;
-       }
-
-       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 set_query (c_psql_database_t *db, const char *name)
-{
-       c_psql_query_t *query;
-
-       query = c_psql_query_get (name, -1);
-       if (NULL == query) {
-               log_err ("Query \"%s\" not found - please check your configuration.",
-                               name);
-               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;
+       data->params_num++;
+       udb_query_set_user_data (q, data);
 
-       db->queries[db->queries_num - 1] = query;
-       return 0;
-} /* set_query */
+       return (0);
+} /* config_query_param_add */
 
-static int config_set_query (c_psql_database_t *db, const oconfig_item_t *ci)
+static int config_query_callback (udb_query_t *q, oconfig_item_t *ci)
 {
-       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;
-       }
-       return set_query (db, ci->values[0].value.string);
-} /* config_set_query */
+       if (0 == strcasecmp ("Param", ci->key))
+               return config_query_param_add (q, ci);
 
-static int c_psql_config_query (oconfig_item_t *ci)
-{
-       c_psql_query_t *query;
+       log_err ("Option not allowed within a Query block: `%s'", ci->key);
 
-       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_s ("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 if (0 == strcasecmp (c->key, "MinPGVersion"))
-                       config_set_i ("MinPGVersion", &query->min_pg_version, c);
-               else if (0 == strcasecmp (c->key, "MaxPGVersion"))
-                       config_set_i ("MaxPGVersion", &query->max_pg_version, c);
-               else
-                       log_warn ("Ignoring unknown config key \"%s\".", c->key);
-       }
-
-       for (i = 0; i < queries_num - 1; ++i) {
-               c_psql_query_t *q = queries + i;
-
-               if ((0 == strcasecmp (q->name, query->name))
-                               && (q->min_pg_version <= query->max_pg_version)
-                               && (query->min_pg_version <= q->max_pg_version)) {
-                       log_err ("Ignoring redefinition (with overlapping version ranges) "
-                                       "of query \"%s\".", query->name);
-                       c_psql_query_delete (query);
-                       --queries_num;
-                       return 1;
-               }
-       }
-
-       if (query->min_pg_version > query->max_pg_version) {
-               log_err ("Query \"%s\": MinPGVersion > MaxPGVersion.",
-                               query->name);
-               c_psql_query_delete (query);
-               --queries_num;
-               return 1;
-       }
-
-       if (NULL == query->query) {
-               log_err ("Query \"%s\" does not include an SQL query string - "
-                               "please check your configuration.", query->name);
-               c_psql_query_delete (query);
-               --queries_num;
-               return 1;
-       }
-       return 0;
-} /* c_psql_config_query */
+       return (-1);
+} /* config_query_callback */
 
 static int c_psql_config_database (oconfig_item_t *ci)
 {
@@ -849,17 +615,29 @@ static int c_psql_config_database (oconfig_item_t *ci)
                else if (0 == strcasecmp (c->key, "Service"))
                        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) {
-               for (i = 0; i < def_queries_num; ++i)
-                       set_query (db, def_queries[i]);
+       /* 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)
 {
@@ -887,7 +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
@@ -903,4 +683,3 @@ void module_register (void)
 } /* module_register */
 
 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */
-