pangolin_exporter

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// Copyright 2023 The Prometheus Authors
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package collector
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import (
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	"context"
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	"database/sql"
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	"github.com/go-kit/log"
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	"github.com/prometheus/client_golang/prometheus"
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)
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const statioUserTableSubsystem = "statio_user_tables"
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func init() {
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	registerCollector(statioUserTableSubsystem, defaultEnabled, NewPGStatIOUserTablesCollector)
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}
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type PGStatIOUserTablesCollector struct {
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	log log.Logger
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}
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func NewPGStatIOUserTablesCollector(config collectorConfig) (Collector, error) {
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	return &PGStatIOUserTablesCollector{log: config.logger}, nil
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}
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var (
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	statioUserTablesHeapBlksRead = prometheus.NewDesc(
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		prometheus.BuildFQName(namespace, statioUserTableSubsystem, "heap_blocks_read"),
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		"Number of disk blocks read from this table",
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		[]string{"datname", "schemaname", "relname"},
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		prometheus.Labels{},
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	)
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	statioUserTablesHeapBlksHit = prometheus.NewDesc(
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		prometheus.BuildFQName(namespace, statioUserTableSubsystem, "heap_blocks_hit"),
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		"Number of buffer hits in this table",
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		[]string{"datname", "schemaname", "relname"},
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		prometheus.Labels{},
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	)
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	statioUserTablesIdxBlksRead = prometheus.NewDesc(
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		prometheus.BuildFQName(namespace, statioUserTableSubsystem, "idx_blocks_read"),
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		"Number of disk blocks read from all indexes on this table",
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		[]string{"datname", "schemaname", "relname"},
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		prometheus.Labels{},
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	)
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	statioUserTablesIdxBlksHit = prometheus.NewDesc(
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		prometheus.BuildFQName(namespace, statioUserTableSubsystem, "idx_blocks_hit"),
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		"Number of buffer hits in all indexes on this table",
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		[]string{"datname", "schemaname", "relname"},
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		prometheus.Labels{},
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	)
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	statioUserTablesToastBlksRead = prometheus.NewDesc(
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		prometheus.BuildFQName(namespace, statioUserTableSubsystem, "toast_blocks_read"),
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		"Number of disk blocks read from this table's TOAST table (if any)",
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		[]string{"datname", "schemaname", "relname"},
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		prometheus.Labels{},
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	)
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	statioUserTablesToastBlksHit = prometheus.NewDesc(
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		prometheus.BuildFQName(namespace, statioUserTableSubsystem, "toast_blocks_hit"),
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		"Number of buffer hits in this table's TOAST table (if any)",
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		[]string{"datname", "schemaname", "relname"},
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		prometheus.Labels{},
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	)
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	statioUserTablesTidxBlksRead = prometheus.NewDesc(
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		prometheus.BuildFQName(namespace, statioUserTableSubsystem, "tidx_blocks_read"),
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		"Number of disk blocks read from this table's TOAST table indexes (if any)",
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		[]string{"datname", "schemaname", "relname"},
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		prometheus.Labels{},
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	)
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	statioUserTablesTidxBlksHit = prometheus.NewDesc(
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		prometheus.BuildFQName(namespace, statioUserTableSubsystem, "tidx_blocks_hit"),
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		"Number of buffer hits in this table's TOAST table indexes (if any)",
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		[]string{"datname", "schemaname", "relname"},
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		prometheus.Labels{},
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	)
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	statioUserTablesQuery = `SELECT
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		current_database() datname,
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		schemaname,
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		relname,
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		heap_blks_read,
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		heap_blks_hit,
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		idx_blks_read,
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		idx_blks_hit,
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		toast_blks_read,
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		toast_blks_hit,
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		tidx_blks_read,
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		tidx_blks_hit
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	FROM pg_statio_user_tables`
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)
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func (PGStatIOUserTablesCollector) Update(ctx context.Context, instance *instance, ch chan<- prometheus.Metric) error {
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	db := instance.getDB()
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	rows, err := db.QueryContext(ctx,
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		statioUserTablesQuery)
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	if err != nil {
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		return err
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	}
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	defer rows.Close()
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	for rows.Next() {
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		var datname, schemaname, relname sql.NullString
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		var heapBlksRead, heapBlksHit, idxBlksRead, idxBlksHit, toastBlksRead, toastBlksHit, tidxBlksRead, tidxBlksHit sql.NullInt64
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		if err := rows.Scan(&datname, &schemaname, &relname, &heapBlksRead, &heapBlksHit, &idxBlksRead, &idxBlksHit, &toastBlksRead, &toastBlksHit, &tidxBlksRead, &tidxBlksHit); err != nil {
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			return err
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		}
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		datnameLabel := "unknown"
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		if datname.Valid {
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			datnameLabel = datname.String
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		}
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		schemanameLabel := "unknown"
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		if schemaname.Valid {
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			schemanameLabel = schemaname.String
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		}
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		relnameLabel := "unknown"
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		if relname.Valid {
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			relnameLabel = relname.String
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		}
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		heapBlksReadMetric := 0.0
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		if heapBlksRead.Valid {
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			heapBlksReadMetric = float64(heapBlksRead.Int64)
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		}
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		ch <- prometheus.MustNewConstMetric(
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			statioUserTablesHeapBlksRead,
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			prometheus.CounterValue,
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			heapBlksReadMetric,
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			datnameLabel, schemanameLabel, relnameLabel,
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		)
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		heapBlksHitMetric := 0.0
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		if heapBlksHit.Valid {
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			heapBlksHitMetric = float64(heapBlksHit.Int64)
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		}
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		ch <- prometheus.MustNewConstMetric(
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			statioUserTablesHeapBlksHit,
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			prometheus.CounterValue,
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			heapBlksHitMetric,
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			datnameLabel, schemanameLabel, relnameLabel,
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		)
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		idxBlksReadMetric := 0.0
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		if idxBlksRead.Valid {
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			idxBlksReadMetric = float64(idxBlksRead.Int64)
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		}
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		ch <- prometheus.MustNewConstMetric(
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			statioUserTablesIdxBlksRead,
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			prometheus.CounterValue,
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			idxBlksReadMetric,
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			datnameLabel, schemanameLabel, relnameLabel,
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		)
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		idxBlksHitMetric := 0.0
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		if idxBlksHit.Valid {
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			idxBlksHitMetric = float64(idxBlksHit.Int64)
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		}
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		ch <- prometheus.MustNewConstMetric(
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			statioUserTablesIdxBlksHit,
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			prometheus.CounterValue,
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			idxBlksHitMetric,
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			datnameLabel, schemanameLabel, relnameLabel,
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		)
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		toastBlksReadMetric := 0.0
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		if toastBlksRead.Valid {
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			toastBlksReadMetric = float64(toastBlksRead.Int64)
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		}
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		ch <- prometheus.MustNewConstMetric(
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			statioUserTablesToastBlksRead,
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			prometheus.CounterValue,
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			toastBlksReadMetric,
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			datnameLabel, schemanameLabel, relnameLabel,
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		)
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		toastBlksHitMetric := 0.0
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		if toastBlksHit.Valid {
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			toastBlksHitMetric = float64(toastBlksHit.Int64)
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		}
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		ch <- prometheus.MustNewConstMetric(
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			statioUserTablesToastBlksHit,
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			prometheus.CounterValue,
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			toastBlksHitMetric,
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			datnameLabel, schemanameLabel, relnameLabel,
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		)
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		tidxBlksReadMetric := 0.0
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		if tidxBlksRead.Valid {
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			tidxBlksReadMetric = float64(tidxBlksRead.Int64)
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		}
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		ch <- prometheus.MustNewConstMetric(
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			statioUserTablesTidxBlksRead,
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			prometheus.CounterValue,
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			tidxBlksReadMetric,
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			datnameLabel, schemanameLabel, relnameLabel,
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		)
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		tidxBlksHitMetric := 0.0
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		if tidxBlksHit.Valid {
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			tidxBlksHitMetric = float64(tidxBlksHit.Int64)
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		}
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		ch <- prometheus.MustNewConstMetric(
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			statioUserTablesTidxBlksHit,
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			prometheus.CounterValue,
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			tidxBlksHitMetric,
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			datnameLabel, schemanameLabel, relnameLabel,
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		)
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	}
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	return rows.Err()
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}
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