Deletes extra junk indexes created by Sequelize when using alter: true

delete_sequelize_junk_indexes.js

// https://github.com/sequelize/sequelize/issues/8984#issuecomment-738790473
// Here is a workaround to delete new indices after calling sequelize.sync({alter: true});
// Be careful, this will delete all indices of the current database that ends with a number after an underline character (e.g. index_1)

const rawTables = await this.sequelize.query("SHOW TABLES")
const tables = rawTables[0].map(i => i[Object.keys(rawTables[0][0])[0]])

for (const t of tables) {
    
    const rawKeys = await this.sequelize.query(`SHOW INDEX FROM ${t}`)
    const keys = rawKeys[0].map(i => i["Key_name"]).filter(i => i.match(/[a-zA-Z]+_\d+/))
    
    for (const k of keys) {
        console.log('Deleting index', t, '->', k)
        await this.sequelize.query(`ALTER TABLE ${t} DROP INDEX ${k}`)
    }
    
}