Set db connection to UTC - Fix hashrate indexing

backend/src/api/database-migration.ts

@@ -6,7 +6,7 @@ import logger from '../logger';
 const sleep = (ms: number) => new Promise(res => setTimeout(res, ms));
 
 class DatabaseMigration {
-  private static currentVersion = 13;
+  private static currentVersion = 14;
   private queryTimeout = 120000;
   private statisticsAddedIndexed = false;
 
@@ -77,7 +77,7 @@ class DatabaseMigration {
     await this.$setStatisticsAddedIndexedFlag(databaseSchemaVersion);
 
     const isBitcoin = ['mainnet', 'testnet', 'signet'].includes(config.MEMPOOL.NETWORK);
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       await this.$executeQuery(connection, this.getCreateElementsTableQuery(), await this.$checkIfTableExists('elements_pegs'));
       await this.$executeQuery(connection, this.getCreateStatisticsQuery(), await this.$checkIfTableExists('statistics'));
@@ -168,6 +168,13 @@ class DatabaseMigration {
         await this.$executeQuery(connection, 'ALTER TABLE blocks MODIFY `avg_fee_rate` BIGINT UNSIGNED NOT NULL DEFAULT "0"');
       }
 
+      if (databaseSchemaVersion < 14 && isBitcoin === true) {
+        logger.warn(`'hashrates' table has been truncated. Re-indexing from scratch.`);
+        await this.$executeQuery(connection, 'TRUNCATE hashrates;'); // Need to re-index
+        await this.$executeQuery(connection, 'ALTER TABLE `hashrates` DROP FOREIGN KEY `hashrates_ibfk_1`');
+        await this.$executeQuery(connection, 'ALTER TABLE `hashrates` MODIFY `pool_id` SMALLINT UNSIGNED NOT NULL DEFAULT "0"');
+      }
+
       connection.release();
     } catch (e) {
       connection.release();
@@ -187,7 +194,7 @@ class DatabaseMigration {
       return;
     }
 
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
 
     try {
       // We don't use "CREATE INDEX IF NOT EXISTS" because it is not supported on old mariadb version 5.X
@@ -225,7 +232,7 @@ class DatabaseMigration {
    * Check if 'table' exists in the database
    */
   private async $checkIfTableExists(table: string): Promise<boolean> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const query = `SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = '${config.DATABASE.DATABASE}' AND TABLE_NAME = '${table}'`;
     const [rows] = await connection.query<any>({ sql: query, timeout: this.queryTimeout });
     connection.release();
@@ -236,7 +243,7 @@ class DatabaseMigration {
    * Get current database version
    */
   private async $getSchemaVersionFromDatabase(): Promise<number> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const query = `SELECT number FROM state WHERE name = 'schema_version';`;
     const [rows] = await this.$executeQuery(connection, query, true);
     connection.release();
@@ -247,7 +254,7 @@ class DatabaseMigration {
    * Create the `state` table
    */
   private async $createMigrationStateTable(): Promise<void> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
 
     try {
       const query = `CREATE TABLE IF NOT EXISTS state (
@@ -279,7 +286,7 @@ class DatabaseMigration {
     }
     transactionQueries.push(this.getUpdateToLatestSchemaVersionQuery());
 
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       await this.$executeQuery(connection, 'START TRANSACTION;');
       for (const query of transactionQueries) {
@@ -330,7 +337,7 @@ class DatabaseMigration {
    * Print current database version
    */
   private async $printDatabaseVersion() {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows] = await this.$executeQuery(connection, 'SELECT VERSION() as version;', true);
       logger.debug(`MIGRATIONS: Database engine version '${rows[0].version}'`);
@@ -474,7 +481,7 @@ class DatabaseMigration {
   public async $truncateIndexedData(tables: string[]) {
     const allowedTables = ['blocks', 'hashrates'];
 
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       for (const table of tables) {
         if (!allowedTables.includes(table)) {

backend/src/api/liquid/elements-parser.ts

@@ -33,7 +33,7 @@ class ElementsParser {
   }
 
   public async $getPegDataByMonth(): Promise<any> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const query = `SELECT SUM(amount) AS amount, DATE_FORMAT(FROM_UNIXTIME(datetime), '%Y-%m-01') AS date FROM elements_pegs GROUP BY DATE_FORMAT(FROM_UNIXTIME(datetime), '%Y%m')`;
     const [rows] = await connection.query<any>(query);
     connection.release();
@@ -79,7 +79,7 @@ class ElementsParser {
 
   protected async $savePegToDatabase(height: number, blockTime: number, amount: number, txid: string,
     txindex: number, bitcoinaddress: string, bitcointxid: string, bitcoinindex: number, final_tx: number): Promise<void> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const query = `INSERT INTO elements_pegs(
         block, datetime, amount, txid, txindex, bitcoinaddress, bitcointxid, bitcoinindex, final_tx
       ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`;
@@ -93,7 +93,7 @@ class ElementsParser {
   }
 
   protected async $getLatestBlockHeightFromDatabase(): Promise<number> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const query = `SELECT number FROM state WHERE name = 'last_elements_block'`;
     const [rows] = await connection.query<any>(query);
     connection.release();
@@ -101,7 +101,7 @@ class ElementsParser {
   }
 
   protected async $saveLatestBlockToDatabase(blockHeight: number) {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const query = `UPDATE state SET number = ? WHERE name = 'last_elements_block'`;
     await connection.query<any>(query, [blockHeight]);
     connection.release();

backend/src/api/mining.ts

@@ -80,8 +80,8 @@ class Mining {
 
     // We only run this once a week
     const latestTimestamp = await HashratesRepository.$getLatestRunTimestamp('last_weekly_hashrates_indexing');
-    const now = new Date().getTime() / 1000;
+    const now = new Date();
-    if (now - latestTimestamp < 604800) {
+    if ((now.getTime() / 1000) - latestTimestamp < 604800) {
       return;
     }
 
@@ -94,7 +94,6 @@ class Mining {
       const hashrates: any[] = [];
       const genesisTimestamp = 1231006505; // bitcoin-cli getblock 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f
 
-      const now = new Date();
       const lastMonday = new Date(now.setDate(now.getDate() - (now.getDay() + 6) % 7));
       const lastMondayMidnight = this.getDateMidnight(lastMonday);
       let toTimestamp = Math.round((lastMondayMidnight.getTime() - 604800) / 1000);
@@ -108,7 +107,7 @@ class Mining {
         const fromTimestamp = toTimestamp - 604800;
 
         // Skip already indexed weeks
-        if (indexedTimestamp.includes(toTimestamp + 1)) {
+        if (indexedTimestamp.includes(toTimestamp)) {
           toTimestamp -= 604800;
           ++totalIndexed;
           continue;
@@ -133,7 +132,7 @@ class Mining {
 
         for (const pool of pools) {
           hashrates.push({
-            hashrateTimestamp: toTimestamp + 1,
+            hashrateTimestamp: toTimestamp,
             avgHashrate: pool['hashrate'],
             poolId: pool.poolId,
             share: pool['share'],
@@ -202,7 +201,7 @@ class Mining {
         const fromTimestamp = toTimestamp - 86400;
 
         // Skip already indexed weeks
-        if (indexedTimestamp.includes(fromTimestamp)) {
+        if (indexedTimestamp.includes(toTimestamp)) {
           toTimestamp -= 86400;
           ++totalIndexed;
           continue;
@@ -220,7 +219,7 @@ class Mining {
         hashrates.push({
           hashrateTimestamp: toTimestamp,
           avgHashrate: lastBlockHashrate,
-          poolId: null,
+          poolId: 0,
           share: 1,
           type: 'daily',
         });

backend/src/api/pools-parser.ts

@@ -66,7 +66,7 @@ class PoolsParser {
     logger.debug(`Found ${poolNames.length} unique mining pools`);
 
     // Get existing pools from the db
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     let existingPools;
     try {
       [existingPools] = await connection.query<any>({ sql: 'SELECT * FROM pools;', timeout: 120000 });
@@ -152,7 +152,7 @@ class PoolsParser {
    * Manually add the 'unknown pool'
    */
   private async insertUnknownPool() {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows]: any[] = await connection.query({ sql: 'SELECT name from pools where name="Unknown"', timeout: 120000 });
       if (rows.length === 0) {

backend/src/api/statistics.ts

@@ -155,7 +155,7 @@ class Statistics {
   }
 
   private async $createZeroedStatistic(): Promise<number | undefined> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const query = `INSERT INTO statistics(
               added,
@@ -216,7 +216,7 @@ class Statistics {
   }
 
   private async $create(statistics: Statistic): Promise<number | undefined> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const query = `INSERT INTO statistics(
               added,
@@ -421,7 +421,7 @@ class Statistics {
 
   private async $get(id: number): Promise<OptimizedStatistic | undefined> {
     try {
-      const connection = await DB.pool.getConnection();
+      const connection = await DB.getConnection();
       const query = `SELECT *, UNIX_TIMESTAMP(added) as added FROM statistics WHERE id = ?`;
       const [rows] = await connection.query<any>(query, [id]);
       connection.release();
@@ -435,7 +435,7 @@ class Statistics {
 
   public async $list2H(): Promise<OptimizedStatistic[]> {
     try {
-      const connection = await DB.pool.getConnection();
+      const connection = await DB.getConnection();
       const query = `SELECT *, UNIX_TIMESTAMP(added) as added FROM statistics ORDER BY statistics.added DESC LIMIT 120`;
       const [rows] = await connection.query<any>({ sql: query, timeout: this.queryTimeout });
       connection.release();
@@ -448,7 +448,7 @@ class Statistics {
 
   public async $list24H(): Promise<OptimizedStatistic[]> {
     try {
-      const connection = await DB.pool.getConnection();
+      const connection = await DB.getConnection();
       const query = `SELECT *, UNIX_TIMESTAMP(added) as added FROM statistics ORDER BY statistics.added DESC LIMIT 1440`;
       const [rows] = await connection.query<any>({ sql: query, timeout: this.queryTimeout });
       connection.release();
@@ -461,7 +461,7 @@ class Statistics {
 
   public async $list1W(): Promise<OptimizedStatistic[]> {
     try {
-      const connection = await DB.pool.getConnection();
+      const connection = await DB.getConnection();
       const query = this.getQueryForDaysAvg(300, '1 WEEK'); // 5m interval
       const [rows] = await connection.query<any>({ sql: query, timeout: this.queryTimeout });
       connection.release();
@@ -474,7 +474,7 @@ class Statistics {
 
   public async $list1M(): Promise<OptimizedStatistic[]> {
     try {
-      const connection = await DB.pool.getConnection();
+      const connection = await DB.getConnection();
       const query = this.getQueryForDaysAvg(1800, '1 MONTH'); // 30m interval
       const [rows] = await connection.query<any>({ sql: query, timeout: this.queryTimeout });
       connection.release();
@@ -487,7 +487,7 @@ class Statistics {
 
   public async $list3M(): Promise<OptimizedStatistic[]> {
     try {
-      const connection = await DB.pool.getConnection();
+      const connection = await DB.getConnection();
       const query = this.getQueryForDaysAvg(7200, '3 MONTH'); // 2h interval
       const [rows] = await connection.query<any>({ sql: query, timeout: this.queryTimeout });
       connection.release();
@@ -500,7 +500,7 @@ class Statistics {
 
   public async $list6M(): Promise<OptimizedStatistic[]> {
     try {
-      const connection = await DB.pool.getConnection();
+      const connection = await DB.getConnection();
       const query = this.getQueryForDaysAvg(10800, '6 MONTH'); // 3h interval 
       const [rows] = await connection.query<any>({ sql: query, timeout: this.queryTimeout });
       connection.release();
@@ -513,7 +513,7 @@ class Statistics {
 
   public async $list1Y(): Promise<OptimizedStatistic[]> {
     try {
-      const connection = await DB.pool.getConnection();
+      const connection = await DB.getConnection();
       const query = this.getQueryForDays(28800, '1 YEAR'); // 8h interval
       const [rows] = await connection.query<any>({ sql: query, timeout: this.queryTimeout });
       connection.release();
@@ -526,7 +526,7 @@ class Statistics {
 
   public async $list2Y(): Promise<OptimizedStatistic[]> {
     try {
-      const connection = await DB.pool.getConnection();
+      const connection = await DB.getConnection();
       const query = this.getQueryForDays(28800, "2 YEAR"); // 8h interval
       const [rows] = await connection.query<any>({ sql: query, timeout: this.queryTimeout });
       connection.release();
@@ -539,7 +539,7 @@ class Statistics {
 
   public async $list3Y(): Promise<OptimizedStatistic[]> {
     try {
-      const connection = await DB.pool.getConnection();
+      const connection = await DB.getConnection();
       const query = this.getQueryForDays(43200, "3 YEAR"); // 12h interval
       const [rows] = await connection.query<any>({ sql: query, timeout: this.queryTimeout });
       connection.release();

backend/src/database.ts

@@ -1,5 +1,5 @@
 import config from './config';
-import { createPool } from 'mysql2/promise';
+import { createPool, PoolConnection } from 'mysql2/promise';
 import logger from './logger';
 
 export class DB {
@@ -11,13 +11,24 @@ export class DB {
     password: config.DATABASE.PASSWORD,
     connectionLimit: 10,
     supportBigNumbers: true,
-    timezone: '+00:00',
   });
+
+  static connectionsReady: number[] = [];
+
+  static async getConnection() {
+    const connection: PoolConnection = await DB.pool.getConnection();
+    const connectionId = connection['connection'].connectionId;
+    if (!DB.connectionsReady.includes(connectionId)) {
+      await connection.query(`SET time_zone='+00:00';`);
+      this.connectionsReady.push(connectionId);
+    }
+    return connection;
+  }
 }
 
 export async function checkDbConnection() {
   try {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     logger.info('Database connection established.');
     connection.release();
   } catch (e) {

backend/src/index.ts

@@ -5,7 +5,7 @@ import * as WebSocket from 'ws';
 import * as cluster from 'cluster';
 import axios from 'axios';
 
-import { checkDbConnection } from './database';
+import { checkDbConnection, DB } from './database';
 import config from './config';
 import routes from './routes';
 import blocks from './api/blocks';
@@ -180,8 +180,8 @@ class Server {
 
     try {
       blocks.$generateBlockDatabase();
-      mining.$generateNetworkHashrateHistory();
+      await mining.$generateNetworkHashrateHistory();
-      mining.$generatePoolHashrateHistory();
+      await mining.$generatePoolHashrateHistory();
     } catch (e) {
       logger.err(`Unable to run indexing right now, trying again later. ` + e);
     }

backend/src/repositories/BlocksRepository.ts

@@ -8,7 +8,7 @@ class BlocksRepository {
    * Save indexed block data in the database
    */
   public async $saveBlockInDatabase(block: BlockExtended) {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
 
     try {
       const query = `INSERT INTO blocks(
@@ -70,7 +70,7 @@ class BlocksRepository {
       return [];
     }
 
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows]: any[] = await connection.query(`
         SELECT height
@@ -116,7 +116,7 @@ class BlocksRepository {
 
     query += ` GROUP by pools.id`;
 
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows] = await connection.query(query, params);
       connection.release();
@@ -154,7 +154,7 @@ class BlocksRepository {
     }
 
     // logger.debug(query);
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows] = await connection.query(query, params);
       connection.release();
@@ -194,7 +194,7 @@ class BlocksRepository {
     query += ` blockTimestamp BETWEEN FROM_UNIXTIME('${from}') AND FROM_UNIXTIME('${to}')`;
 
     // logger.debug(query);
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows] = await connection.query(query, params);
       connection.release();
@@ -217,7 +217,7 @@ class BlocksRepository {
       LIMIT 1;`;
 
     // logger.debug(query);
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows]: any[] = await connection.query(query);
       connection.release();
@@ -253,7 +253,7 @@ class BlocksRepository {
       LIMIT 10`;
 
     // logger.debug(query);
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows] = await connection.query(query, params);
       connection.release();
@@ -274,7 +274,7 @@ class BlocksRepository {
    * Get one block by height
    */
   public async $getBlockByHeight(height: number): Promise<object | null> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows]: any[] = await connection.query(`
         SELECT *, UNIX_TIMESTAMP(blocks.blockTimestamp) as blockTimestamp,
@@ -305,7 +305,7 @@ class BlocksRepository {
   public async $getBlocksDifficulty(interval: string | null): Promise<object[]> {
     interval = Common.getSqlInterval(interval);
 
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
 
     // :D ... Yeah don't ask me about this one https://stackoverflow.com/a/40303162
     // Basically, using temporary user defined fields, we are able to extract all
@@ -356,7 +356,7 @@ class BlocksRepository {
   }
 
   public async $getOldestIndexedBlockHeight(): Promise<number> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows]: any[] = await connection.query(`SELECT MIN(height) as minHeight FROM blocks`);
       connection.release();

backend/src/repositories/HashratesRepository.ts

@@ -20,9 +20,9 @@ class HashratesRepository {
     }
     query = query.slice(0, -1);
 
-    const connection = await DB.pool.getConnection();
+    let connection;
     try {
-      // logger.debug(query);
+      connection = await DB.getConnection();
       await connection.query(query);
       connection.release();
     } catch (e: any) {
@@ -35,18 +35,16 @@ class HashratesRepository {
   public async $getNetworkDailyHashrate(interval: string | null): Promise<any[]> {
     interval = Common.getSqlInterval(interval);
 
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
 
     let query = `SELECT UNIX_TIMESTAMP(hashrate_timestamp) as timestamp, avg_hashrate as avgHashrate
       FROM hashrates`;
 
     if (interval) {
       query += ` WHERE hashrate_timestamp BETWEEN DATE_SUB(NOW(), INTERVAL ${interval}) AND NOW()
-        AND hashrates.type = 'daily'
+        AND hashrates.type = 'daily'`;
-        AND pool_id IS NULL`;
     } else {
-      query += ` WHERE hashrates.type = 'daily'
+      query += ` WHERE hashrates.type = 'daily'`;
-        AND pool_id IS NULL`;
     }
 
     query += ` ORDER by hashrate_timestamp`;
@@ -64,9 +62,12 @@ class HashratesRepository {
   }
 
   public async $getWeeklyHashrateTimestamps(): Promise<number[]> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
 
-    const query = `SELECT UNIX_TIMESTAMP(hashrate_timestamp) as timestamp FROM hashrates where type = 'weekly' GROUP BY hashrate_timestamp`;
+    const query = `SELECT UNIX_TIMESTAMP(hashrate_timestamp) as timestamp
+      FROM hashrates
+      WHERE type = 'weekly'
+      GROUP BY hashrate_timestamp`;
 
     try {
       const [rows]: any[] = await connection.query(query);
@@ -86,7 +87,7 @@ class HashratesRepository {
   public async $getPoolsWeeklyHashrate(interval: string | null): Promise<any[]> {
     interval = Common.getSqlInterval(interval);
 
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const topPoolsId = (await PoolsRepository.$getPoolsInfo('1w')).map((pool) => pool.poolId);
 
     let query = `SELECT UNIX_TIMESTAMP(hashrate_timestamp) as timestamp, avg_hashrate as avgHashrate, share, pools.name as poolName
@@ -120,7 +121,7 @@ class HashratesRepository {
    * Returns a pool hashrate history
    */
    public async $getPoolWeeklyHashrate(poolId: number): Promise<any[]> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
 
     // Find hashrate boundaries
     let query = `SELECT MIN(hashrate_timestamp) as firstTimestamp, MAX(hashrate_timestamp) as lastTimestamp
@@ -163,7 +164,7 @@ class HashratesRepository {
   }
 
   public async $setLatestRunTimestamp(key: string, val: any = null) {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const query = `UPDATE state SET number = ? WHERE name = ?`;
 
     try {
@@ -175,7 +176,7 @@ class HashratesRepository {
   }
 
   public async $getLatestRunTimestamp(key: string): Promise<number> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const query = `SELECT number FROM state WHERE name = ?`;
 
     try {

backend/src/repositories/PoolsRepository.ts

@@ -8,7 +8,7 @@ class PoolsRepository {
    * Get all pools tagging info
    */
   public async $getPools(): Promise<PoolTag[]> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const [rows] = await connection.query('SELECT id, name, addresses, regexes FROM pools;');
     connection.release();
     return <PoolTag[]>rows;
@@ -18,7 +18,7 @@ class PoolsRepository {
    * Get unknown pool tagging info
    */
   public async $getUnknownPool(): Promise<PoolTag> {
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     const [rows] = await connection.query('SELECT id, name FROM pools where name = "Unknown"');
     connection.release();
     return <PoolTag>rows[0];
@@ -42,7 +42,7 @@ class PoolsRepository {
       ORDER BY COUNT(height) DESC`;
 
     // logger.debug(query);
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows] = await connection.query(query);
       connection.release();
@@ -64,7 +64,7 @@ class PoolsRepository {
       LEFT JOIN blocks on pools.id = blocks.pool_id AND blocks.blockTimestamp BETWEEN FROM_UNIXTIME(?) AND FROM_UNIXTIME(?)
       GROUP BY pools.id`;
 
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows] = await connection.query(query, [from, to]);
       connection.release();
@@ -87,7 +87,7 @@ class PoolsRepository {
       WHERE pools.id = ?`;
 
     // logger.debug(query);
-    const connection = await DB.pool.getConnection();
+    const connection = await DB.getConnection();
     try {
       const [rows] = await connection.query(query, [poolId]);
       connection.release();