From dea378014dd45bf90f51a599b4a801e0bc22059f Mon Sep 17 00:00:00 2001
From: Fabio Di Stasio <fabio286@gmail.com>
Date: Wed, 4 Aug 2021 15:52:26 +0200
Subject: [PATCH] perf: approximate table total updated on table refresh

---
 src/main/ipc-handlers/tables.js               | 10 +++++++
 src/main/libs/clients/MySQLClient.js          | 13 +++++++++
 src/main/libs/clients/PostgreSQLClient.js     | 13 +++++++++
 .../WorkspaceExploreBarTableContext.vue       |  2 +-
 src/renderer/components/WorkspaceTableTab.vue | 28 +++++++++++++++----
 src/renderer/ipc-api/Tables.js                |  4 +++
 6 files changed, 63 insertions(+), 7 deletions(-)

diff --git a/src/main/ipc-handlers/tables.js b/src/main/ipc-handlers/tables.js
index 8c9799c2..7716d4ac 100644
--- a/src/main/ipc-handlers/tables.js
+++ b/src/main/ipc-handlers/tables.js
@@ -38,6 +38,16 @@ export default (connections) => {
       }
    });
 
+   ipcMain.handle('get-table-count', async (event, params) => {
+      try {
+         const result = await connections[params.uid].getTableApproximateCount(params);
+         return { status: 'success', response: result };
+      }
+      catch (err) {
+         return { status: 'error', response: err.toString() };
+      }
+   });
+
    ipcMain.handle('get-table-indexes', async (event, params) => {
       try {
          const result = await connections[params.uid].getTableIndexes(params);
diff --git a/src/main/libs/clients/MySQLClient.js b/src/main/libs/clients/MySQLClient.js
index 4deb60d2..03fe2ebf 100644
--- a/src/main/libs/clients/MySQLClient.js
+++ b/src/main/libs/clients/MySQLClient.js
@@ -424,6 +424,19 @@ export class MySQLClient extends AntaresCore {
       });
    }
 
+   /**
+    * @param {Object} params
+    * @param {String} params.schema
+    * @param {String} params.table
+    * @returns {Object} table row count
+    * @memberof MySQLClient
+    */
+   async getTableApproximateCount ({ schema, table }) {
+      const { rows } = await this.raw(`SELECT table_rows "count" FROM information_schema.tables WHERE table_name = "${table}" AND table_schema = "${schema}"`);
+
+      return rows.length ? rows[0].count : 0;
+   }
+
    /**
     * @param {Object} params
     * @param {String} params.schema
diff --git a/src/main/libs/clients/PostgreSQLClient.js b/src/main/libs/clients/PostgreSQLClient.js
index 01cd42e8..5bc1f6e5 100644
--- a/src/main/libs/clients/PostgreSQLClient.js
+++ b/src/main/libs/clients/PostgreSQLClient.js
@@ -293,6 +293,19 @@ export class PostgreSQLClient extends AntaresCore {
       });
    }
 
+   /**
+    * @param {Object} params
+    * @param {String} params.schema
+    * @param {String} params.table
+    * @returns {Object} table row count
+    * @memberof PostgreSQLClient
+    */
+   async getTableApproximateCount ({ schema, table }) {
+      const { rows } = await this.raw(`SELECT reltuples AS count FROM pg_class WHERE relname = '${table}'`);
+
+      return rows.length ? rows[0].count : 0;
+   }
+
    /**
     * @param {Object} params
     * @param {String} params.schema
diff --git a/src/renderer/components/WorkspaceExploreBarTableContext.vue b/src/renderer/components/WorkspaceExploreBarTableContext.vue
index 06a22389..dff44ef7 100644
--- a/src/renderer/components/WorkspaceExploreBarTableContext.vue
+++ b/src/renderer/components/WorkspaceExploreBarTableContext.vue
@@ -104,7 +104,7 @@ export default {
          return this.getWorkspace(this.selectedWorkspace);
       },
       customizations () {
-         return this.workspace ? this.workspace.customizations : {};
+         return this.workspace && this.workspace.customizations ? this.workspace.customizations : {};
       }
    },
    methods: {
diff --git a/src/renderer/components/WorkspaceTableTab.vue b/src/renderer/components/WorkspaceTableTab.vue
index 63e03e21..cb4f0f9d 100644
--- a/src/renderer/components/WorkspaceTableTab.vue
+++ b/src/renderer/components/WorkspaceTableTab.vue
@@ -112,8 +112,8 @@
                <div v-if="results.length && results[0].rows">
                   {{ $t('word.results') }}: <b>{{ results[0].rows.length | localeString }}</b>
                </div>
-               <div v-if="hasApproximately || (page > 1 && tableInfo.rows)">
-                  {{ $t('word.total') }}: <b>{{ tableInfo.rows | localeString }}</b> <small>({{ $t('word.approximately') }})</small>
+               <div v-if="hasApproximately || (page > 1 && approximateCount)">
+                  {{ $t('word.total') }}: <b :title="$t('word.approximately')">≈ {{ approximateCount | localeString }}</b>
                </div>
                <div class="d-flex" :title="$t('word.schema')">
                   <i class="mdi mdi-18px mdi-database mr-1" /><b>{{ schema }}</b>
@@ -175,7 +175,7 @@ export default {
    },
    filters: {
       localeString (val) {
-         if (val)
+         if (val !== null)
             return val.toLocaleString();
       }
    },
@@ -200,7 +200,8 @@ export default {
          refreshInterval: null,
          sortParams: {},
          page: 1,
-         pageProxy: 1
+         pageProxy: 1,
+         approximateCount: 0
       };
    },
    computed: {
@@ -232,15 +233,15 @@ export default {
       hasApproximately () {
          return this.results.length &&
             this.results[0].rows &&
-            this.tableInfo &&
             this.results[0].rows.length === this.limit &&
-            this.results[0].rows.length < this.tableInfo.rows;
+            this.results[0].rows.length < this.approximateCount;
       }
    },
    watch: {
       schema () {
          if (this.isSelected) {
             this.page = 1;
+            this.approximateCount = 0;
             this.sortParams = {};
             this.getTableData();
             this.lastTable = this.table;
@@ -250,6 +251,7 @@ export default {
       table () {
          if (this.isSelected) {
             this.page = 1;
+            this.approximateCount = 0;
             this.sortParams = {};
             this.getTableData();
             this.lastTable = this.table;
@@ -315,6 +317,20 @@ export default {
             this.addNotification({ status: 'error', message: err.stack });
          }
 
+         if (this.results.length && this.results[0].rows.length === this.limit) {
+            try { // Table approximate count
+               const { status, response } = await Tables.getTableApproximateCount(params);
+
+               if (status === 'success')
+                  this.approximateCount = response;
+               else
+                  this.addNotification({ status: 'error', message: response });
+            }
+            catch (err) {
+               this.addNotification({ status: 'error', message: err.stack });
+            }
+         }
+
          this.isQuering = false;
       },
       getTable () {
diff --git a/src/renderer/ipc-api/Tables.js b/src/renderer/ipc-api/Tables.js
index 25dd8d27..56e93328 100644
--- a/src/renderer/ipc-api/Tables.js
+++ b/src/renderer/ipc-api/Tables.js
@@ -10,6 +10,10 @@ export default class {
       return ipcRenderer.invoke('get-table-data', params);
    }
 
+   static getTableApproximateCount (params) {
+      return ipcRenderer.invoke('get-table-count', params);
+   }
+
    static getTableIndexes (params) {
       return ipcRenderer.invoke('get-table-indexes', params);
    }