From fb591e79e071368b69fb306f70ae214ade0b8515 Mon Sep 17 00:00:00 2001
From: Michael Zanetti <michael_zanetti@gmx.net>
Date: Thu, 22 Sep 2022 13:00:47 +0200
Subject: [PATCH] Create SQL indices on energy log DB for improved resampling
 performance

This speeds up resampling at startup by approx 15 times.
---
 plugin/energylogger.cpp | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/plugin/energylogger.cpp b/plugin/energylogger.cpp
index 83d180c..71877cd 100644
--- a/plugin/energylogger.cpp
+++ b/plugin/energylogger.cpp
@@ -7,6 +7,7 @@
 #include <QSqlQuery>
 #include <QSqlError>
 #include <QSqlRecord>
+#include <QSqlIndex>
 #include <QSettings>
 
 #include <QLoggingCategory>
@@ -453,6 +454,11 @@ bool EnergyLogger::initDB()
             return false;
         }
     }
+    m_db.exec("CREATE INDEX IF NOT EXISTS idx_powerBalance ON powerBalance(sampleRate, timestamp);");
+    if (m_db.lastError().isValid()) {
+        qCWarning(dcEnergyExperience()) << "Error creating powerBalance table index in energy log database. Driver error:" << m_db.lastError().driverText() << "Database error:" << m_db.lastError().databaseText();
+        return false;
+    }
 
     if (!m_db.tables().contains("thingPower")) {
         qCDebug(dcEnergyExperience()) << "No \"thingPower\" table in database. Creating it.";
@@ -470,6 +476,11 @@ bool EnergyLogger::initDB()
             return false;
         }
     }
+    m_db.exec("CREATE INDEX IF NOT EXISTS idx_thingPower ON thingPower(thingId, sampleRate, timestamp);");
+    if (m_db.lastError().isValid()) {
+        qCWarning(dcEnergyExperience()) << "Error creating thingPower table index in energy log database. Driver error:" << m_db.lastError().driverText() << "Database error:" << m_db.lastError().databaseText();
+        return false;
+    }
 
     if (!m_db.tables().contains("thingCache")) {
         qCDebug(dcEnergyExperience()) << "No \"thingCache\" table in database. Creating it.";