mysql-plus v0.16.2
mysql-plus
A MySQL client for Node.js that makes defining tables easy and automatically migrates table schemas.
This module extends the popular mysql module, so it is recommended that you read the mysql documentation, especially the sections on connection options, performing queries, escaping query values, and escaping query identifiers.
Table of Contents
Installation
npm install mysql-plus
# or
yarn add mysql-plusUsage Example
db.js
const mysql = require('mysql-plus');
const pool = mysql.createPool({
host: 'localhost',
user: 'username',
password: 'secret',
database: 'my_db',
});
// Both `mysql` and `pool` are 100% compatible with the mysql module
module.exports = pool;User.js
const db = require('./db');
const userTable = db.defineTable('user', {
columns: {
id: db.ColTypes.bigint().unsigned().notNull().primaryKey().autoIncrement(),
email: db.ColTypes.varchar(255).notNull().unique(),
name: db.ColTypes.varchar(63).notNull(),
},
});
const User = {
async insertAndSelectExample() {
const result = await userTable.insert({email: 'newuser@email.com', name: 'newuser'})
const rows = await userTable.select('*', 'WHERE `id` = ?', [result.insertId]))
console.log(rows); // [ { id: 1, email: 'newuser@email.com', name: 'newuser' } ]
return rows[0];
}
};
module.exports = User;app.js (Express example)
const db = require('./db');
const User = require('./User');
const express = require('express');
const app = express();
app.get('/user', async (req, res, next) => {
try {
const user = await User.insertAndSelectExample();
res.send(user);
} catch (err) {
next(err)
}
})
// Sync the table schemas to the database
db.sync((err) => {
if (err) throw err;
// Now the server can be safely started
app.listen(/*...*/);
});API
Modules
Classes
Info
mysql-plus ⇐ mysql
This module.
Extends: mysql See: mysql
- mysql-plus ⇐ mysql
mysql-plus~ColTypes
A namespace that provides the column type methods used to define columns.
See: Column Types
Example:
const mysql = require('mysql-plus');
const pool = mysql.createPool(config);
const userTable = pool.defineTable('user', {
columns: {
id: mysql.ColTypes.bigint().unsigned().notNull().primaryKey(),
created: mysql.ColTypes.datetime(),
}
});mysql-plus~KeyTypes
A namespace that provides the key type methods used to define keys.
See: Key Types
Example:
const mysql = require('mysql-plus');
const pool = mysql.createPool(config);
const userTable = pool.defineTable('user', {
columns: {
id: mysql.ColTypes.bigint().unsigned().notNull().primaryKey(),
uid: mysql.ColTypes.varchar(32).notNull(),
created: mysql.ColTypes.datetime(),
},
keys: [
mysql.KeyTypes.uniqueIndex('uid'),
mysql.KeyTypes.index('created'),
],
});mysql-plus~createPool(config) ⇒ PoolPlus
Just like the original mysql.createPool()
method except it returns a PoolPlus instance and accepts more options.
| Param | Type | Default | Description |
|---|---|---|---|
| config | Object | A configuration object defining MySQL connection options. In addition to the, possible mysql connection options, this object may also have a plusOptions property to configure the PoolPlus instance, it returns. | |
| config.plusOptions | Object | An optional configuration object that may have the following properties: | |
| config.plusOptions.migrationStrategy | string | One of safe, alter, or drop. Please see the migration strategies documentation here. Defaults to safe in production and alter everywhere else. | |
| config.plusOptions.allowAlterInProduction | boolean | false | Setting this to true will allow alter to be used as a migration strategy in production environments. |
| config.plusOptions.debug | boolean | false | If set to true, all of the SQL operations that will be performed will be printed to the console. |
Returns: PoolPlus - A new PoolPlus instance.
Example:
const mysql = require('mysql-plus');
const pool = mysql.createPool({
host: 'example.org',
user: 'me',
password: 'secret',
plusOptions: {
migrationStrategy: 'safe',
allowAlterInProduction: true,
debug: true,
},
});mysql-plus~queryCallback : function
A function called with the results of a query.
| Param | Type | Description |
|---|---|---|
| error | ?Error | An Error object if an error occurred; null otherwise. |
| results | Array | Object | The results of the query. |
| fields | Array.<Object> | Information about the returned results' fields (if any). |
See: https://github.com/mysqljs/mysql#performing-queries
PoolPlus ⇐ Pool
A class that extends the mysql module's Pool class with the ability to define tables
and perform queries and transactions using promises.
Extends: Pool See: Pool
- PoolPlus ⇐ Pool
- instance
- .ColTypes
- .KeyTypes
- .raw(sql) ⇒ Object
- .basicTable(name) ⇒ MySQLTable
- .defineTable(name, schema, [migrationStrategy]) ⇒ MySQLTable
- .sync([cb]) ⇒ Promise
- .pquery(sql, [values], [cb]) ⇒ Promise
- .transaction(trxnHandler) ⇒ Promise
- inner
- ~transactionHandler ⇒ Promise
- instance
poolPlus.ColTypes
A namespace that provides the column type methods used to define columns.
The exact same thing as mysqlPlus.ColTypes.
Just here for convenience.
See: Column Types
Example:
const pool = mysql.createPool(config);
const ColTypes = pool.ColTypes;
const userTable = pool.defineTable('user', {
columns: {
id: ColTypes.bigint().unsigned().notNull().primaryKey(),
created: ColTypes.datetime(),
}
});poolPlus.KeyTypes
A namespace that provides the column type methods used to define keys.
The exact same thing as mysqlPlus.KeyTypes.
Just here for convenience.
See: Key Types
Example:
const pool = mysql.createPool(config);
const {ColTypes, KeyTypes} = pool;
const userTable = pool.defineTable('user', {
columns: {
id: ColTypes.bigint().unsigned().notNull().primaryKey(),
uid: ColTypes.varchar(32).notNull(),
created: ColTypes.datetime(),
},
keys: [
KeyTypes.uniqueIndex('uid'),
KeyTypes.index('created'),
],
});poolPlus.raw(sql) ⇒ Object
Wraps the provided SQL string in an object that will prevent the string from being escaped
when it is used as a data-object value or ? placeholder replacement.
(The same as mysql.raw().)
| Param | Type | Description |
|---|---|---|
| sql | string | SQL that should not be escaped. |
Returns: Object - An object that is turned into the provided sql string when mysql attempts to escape it.
See: (mysql) Escaping query values
Example: Inserting a geometry Point
placeTable.insert({
placeId: 'ChIJK2f',
coordinates: pool.raw('POINT(-80.5204, 43.4642)'),
});
// or
placeTable.insert(
'SET `placeId` = ?, `coordinates` = ?',
['ChIJK2f', pool.raw('POINT(-80.5204, 43.4642)')]
);
// INSERT INTO `place`
// SET `placeId` = 'ChIJK2f', `coordinates` = POINT(-80.5204, 43.4642);poolPlus.basicTable(name) ⇒ MySQLTable
Simply returns an instance of MySQLTable
for querying the table with the given name.
| Param | Type | Description |
|---|---|---|
| name | string | The name of the table. |
Returns: MySQLTable - A MySQLTable instance.
poolPlus.defineTable(name, schema, migrationStrategy) ⇒ MySQLTable
Defines a table to be created or updated in the database.
| Param | Type | Description |
|---|---|---|
| name | string | The name of the table. |
| schema | Object | An object that defines the table's schema. See the Defining Table Schemas section. |
| migrationStrategy | string | One of safe, alter, or drop. This will override the migrationStrategy value from the config (but is still subject to the same restrictions in production environments). |
Returns: MySQLTable - A MySQLTable instance that has methods for performing queries on the table.
See: Defining Table Schemas
Example:
const userTable = pool.defineTable('user', {
columns: {
id: pool.ColTypes.bigint().unsigned().notNull().primaryKey().autoIncrement(),
email: pool.ColTypes.varchar(255).notNull().unique(),
created: pool.ColTypes.datetime(),
}
});poolPlus.sync(cb) ⇒ Promise
Syncs the defined tables to the database by creating new tables and dropping or migrating existing tables (depending on the migration setting).
Generally, this should only be called once when starting up a server.
Warning: If an error occurs while syncing, the database will be in an unknown state. Always keep a backup of your database so you can restore it to the latest working state.
| Param | Type | Description |
|---|---|---|
| cb | function | A callback that is called once all defined table schemas have been synced to the database. If an error occured, the first argument passed to the callback will be the error object. |
Returns: ?Promise - If cb is not provided, a promise will be returned.
Example: With a callback
pool.sync((err) => {
if (err) throw err;
// Now do something such as start an HTTP server
});Example: With a promise
pool.sync()
.then(() => {
// Success
}, (err) => {
// Error
});poolPlus.pquery(sql, values, cb) ⇒ Promise
The same as the query method on the original mysql Pool except when not passed a
callback it returns a promise that resolves with the results of the query.
| Param | Type | Description |
|---|---|---|
| sql | string | Object | An SqlString or options object. |
| values | Array | Values to replace placeholders in the SqlString. |
| cb | queryCallback | An optional callback that gets called with the results of the query. |
Returns: ?Promise - If the cb parameter is omitted, a promise that will resolve with the results
of the query is returned.
See: https://github.com/mysqljs/mysql#performing-queries
Example:
pool.pquery('SELECT * FROM `books` WHERE `author` = "David"')
.then((results) => {
// results will contain the results of the query
})
.catch((error) => {
// error will be the Error that occurred during the query
});poolPlus.transaction(trxnHandler) ⇒ Promise
Begins a transaction and provides a connection to use to make queries during the transaction.
Note: Be aware that there are commands in MySQL that can cause an implicit commit, as described in the MySQL documentation.
| Param | Type | Description |
|---|---|---|
| trxnHandler | transactionHandler | A function that, given a transaction connection, will make queries and then end the transaction. |
Returns: Promise - A promise that is resolved with the results of the transaction (the value
passed to the done() callback or the result of the last returned promise) or is
rejected with the error that caused the transaction to fail.
Example: Using the done callback
pool.transaction((trxn, done) => {
trxn.query('INSERT INTO `animals` VALUES ("dog")', (err, result) => {
if (err) return done(err);
trxn.query(
'INSERT INTO `pets` (`type`,`name`) VALUES (?, "Rover")',
[result.insertId],
done
);
});
}).then(result => {
// result is the result of inserting "Rover" into `pets`
}).catch(err => {
// If this is called then the inserts will have been rolled back
// (so "dog" will not be in the `animals` table)
});Example: Returning a promise
pool.transaction((trxn) => {
return trxn.pquery('INSERT INTO `animals` (`type`) VALUES ("dog")')
.then(result => trxn.pquery(
'INSERT INTO `pets` (`typeID`,`name`) VALUES (?, "Rover")',
[result.insertId]
));
}).then(result => {
// result is the result of inserting "Rover" into `pets`
}).catch(err => {
// An error occurred and the inserts have been rolled back
});PoolPlus~transactionHandler ⇒ Promise
A function that will make queries during a transaction.
| Param | Type | Description |
|---|---|---|
| trxn | Connection | The transaction connection. |
| done | function | A callback that can be used to end the transaction. |
Returns: ?Promise - If not using the done callback, this function must return a promise.
If the promise resolves, the transaction will be committed, and if it rejects, the
transaction will be rolled back. If this function does not return a promise, the
done callback must be used or else the transaction will not be committed and
the transaction connection will never be released.
See: poolPlus.transaction()
Example: To fail a transaction using the done callback
// Call the `done` callback with a truthy value as the first argument
done(error);Example: To complete a transaction using the done callback
// Call the `done` callback with a falsy value as the first argument
// and pass the results of the transaction as the second argument
done(null, results);
done(); // Passing results is not requiredExample: Full example using the done callback
function trxnHandler(trxn, done) {
trxn.query('INSERT INTO `animals` (`type`) VALUES ("dog")', (err, animalsResult) => {
if (err) return done(err);
trxn.query(
'INSERT INTO `pets` (`typeID`,`name`) VALUES (?, "Rover")',
[animalsResult.insertId],
(err, petsResult) => {
if (err) return done(err);
done(null, {animalsResult, petsResult});
}
);
});
}Connection
The mysql module's Connection class extended with one extra method. Returned by
mysql.createConnection()
and pool.getConnection() and
passed to transactionHandler.
connection.pquery(sql, values, cb) ⇒ Promise
The same as the query method except when not passed a callback it returns
a promise that resolves with the results of the query.
| Param | Type | Description |
|---|---|---|
| sql | string | Object | An SqlString or options object. |
| values | Array | Values to replace placeholders in the SqlString. |
| cb | queryCallback | An optional callback that gets called with the results of the query. |
Returns: ?Promise - If the cb parameter is omitted, a promise that will resolve with the results
of the query is returned.
See: https://github.com/mysqljs/mysql#performing-queries
Example:
connection.pquery('SELECT * FROM `books` WHERE `author` = "David"')
.then((results) => {
// results will contain the results of the query
})
.catch((error) => {
// error will be the Error that occurred during the query
});MySQLTable
A class that provides convenient methods for performing queries.To create
an instance, use poolPlus.defineTable() or
poolPlus.basicTable().
See: https://github.com/mysqljs/mysql#performing-queries
- MySQLTable
- .name : string
- .schema : Object
- .pool : PoolPlus
- .trxn : ?Connection
- .select(columns, [sqlString], [values], [cb]) ⇒ Promise
- .exists(sqlString, [values], [cb]) ⇒ Promise
- .insert([data], [sqlString], [values], [cb]) ⇒ Promise
- .insertIfNotExists(data, keyColumns, [cb]) ⇒ Promise
- .update([data], [sqlString], [values], [cb]) ⇒ Promise
- .delete([sqlString], [values], [cb]) ⇒ Promise
- .query() ⇒ Promise
- .transacting(trxn) ⇒ MySQLTable
mySQLTable.name : string
The table's name (as passed to poolPlus.defineTable()).
mySQLTable.schema : Object
The table's schema (as passed to poolPlus.defineTable()).
mySQLTable.pool : PoolPlus
The PoolPlus instance that created this table.
mySQLTable.trxn : ?Connection
The transaction connection that created this table from a call
to table.transacting(trxn).
mySQLTable.select(columns, sqlString, values, cb) ⇒ Promise
Selects data from the table.
| Param | Type | Description |
|---|---|---|
| columns | Array.<string> | string | An array of columns to select or a custom SELECT string. |
| sqlString | string | SQL to be appended to the query after the FROM table clause. |
| values | Array | Values to replace the placeholders in sqlString and columns. |
| cb | queryCallback | A callback that gets called with the results of the query. |
Returns: ?Promise - If the cb parameter is omitted, a promise that will resolve with the results
of the query is returned.
Example: Select all columns
userTable.select('*', (err, rows) => {
if (err) throw err;
// rows contains all data for all users
});
// SELECT * FROM `user`;Example: Select specific columns
userTable.select(['email', 'name'], 'WHERE `points` > 10000', (err, rows) => {
if (err) throw err;
console.log(rows); // -> [{email: 'email@example.com', name: 'John Doe'}, ...]
});
// SELECT `email`, `name` FROM `user` WHERE `points` > 10000;Example: Select with placeholders
userTable.select(['email'], 'WHERE `id` = ?', [5])
.then(rows => console.log(rows)); // -> [{email: 'email@example.com'}]
// SELECT `email` FROM `user` WHERE `id` = 5;
userTable.select('??', 'WHERE ?', ['email', {id: 5}])
.then(rows => console.log(rows)); // -> [{email: 'email@example.com'}]
// SELECT `email` FROM `user` WHERE `id` = 5;Example: Select columns with aliases
userTable.select('`name` AS `fullName`', 'WHERE `points` > 10000')
.then(rows => console.log(rows)); // -> [{fullName: 'John Doe'}, ...]
// SELECT `name` AS `fullName` FROM `user` WHERE `points` > 10000;Example: Select using a function
userTable.select('COUNT(*) AS `highScorers`', 'WHERE `points` > 10000')
.then(rows => console.log(rows)); // -> [{highScorers: 27}]
// SELECT COUNT(*) AS `highScorers` FROM `user` WHERE `points` > 10000;mySQLTable.exists(sqlString, values, cb) ⇒ Promise
Checks if rows in the table exist.
| Param | Type | Description |
|---|---|---|
| sqlString | string | SQL that specifies rows to check for existence. The first example shows how this parameter is used in the query. |
| values | Array | Values to replace the placeholders in sqlString. |
| cb | queryCallback | A callback that gets called with the results of the query where the results will be either true or false. |
Returns: ?Promise - If the cb parameter is omitted, a promise that will
resolve with either true or false is returned.
Example: Using a promise
userTable.exists('WHERE `id` > 10')
.then(exists => console.log(exists)); // true or false
// SELECT EXISTS (
// SELECT 1 FROM `user`
// WHERE `id` > 10 # This is where `sqlString` gets inserted
// LIMIT 1
// )Example: Using a callback and the values argument
userTable.exists('WHERE `id` = ?', [10], (err, exists) => {
if (err) throw err;
console.log(exists); // true or false
});mySQLTable.insert(data, sqlString, values, cb) ⇒ Promise
Inserts data into a new row in the table.
Note: The data and sqlString arguments are individually
optional but at least one of them must be specified.
| Param | Type | Description |
|---|---|---|
| data | Object | Array | An object of (column name)-(data value) pairs or an array containing either 1) an array of arrays of data values or 2) an array of column names and the data array from 1). |
| sqlString | string | SQL to be appended to the query. If data is provided, it is appended directly after the formatted data, otherwise it is appended after "INSERT INTO tableName". |
| values | Array | Values to replace the placeholders in sqlString. |
| cb | queryCallback | A callback that gets called with the results of the query. |
Returns: ?Promise - If the cb parameter is omitted, a promise that will resolve with the results
of the query is returned.
Example: Insert a new user
userTable.insert({email: 'email@example.com', name: 'John Doe'})
.then(result => result.affectedRows); // 1
// INSERT INTO `user`
// SET `email` = 'email@example.com', `name` = 'John Doe';Example: Insert or update
const data = {id: 5, points: 100};
// If duplicate key (id), add the points
const onDuplicateKeySQL = 'ON DUPLICATE KEY UPDATE `points` = `points` + ?';
userTable.insert(data, onDuplicateKeySQL, [data.points])
.then(result => result.affectedRows); // 1 if inserted, 2 if updated
// INSERT INTO `user` SET `id` = 5, `points` = 100
// ON DUPLICATE KEY UPDATE `points` = `points` + 100;Example: With only the sqlString argument
placeTable.insert('SET `location` = POINT(0, 0)');
// INSERT INTO `place` SET `location` = POINT(0, 0);
placeTable.insert('(`location`) VALUES (POINT(?, ?))', [8, 2]);
// INSERT INTO `place` (`location`) VALUES (POINT(8, 2));Example: Bulk insert
const users = [
[1, 'john@email.com', 'John Doe'],
[2, 'jane@email.com', 'Jane Brown'],
];
userTable.insert([users])
.then(result => result.insertId); // 2 (ID of the last inserted row)
// INSERT INTO `user` VALUES
// (1, 'john@email.com', 'John Doe'),
// (2, 'jane@email.com', 'Jane Brown');Example: Bulk insert with specified columns
const users = [
['john@email.com', 'John Doe'],
['jane@email.com', 'Jane Brown'],
];
userTable.insert([['email', 'name'], users])
.then(result => result.affectedRows); // 2
// INSERT INTO `user` (`email`, `name`) VALUES
// ('john@email.com', 'John Doe'),
// ('jane@email.com', 'Jane Brown');mySQLTable.insertIfNotExists(data, keyColumns, cb) ⇒ Promise
Inserts a new row into the table if there are no existing rows in the table that have the same values for the specified columns.
This is useful because if the row is not inserted, the table's
AUTO_INCREMENT value is not increased (unlike when an insert
fails because of a unique key constraint).
| Param | Type | Description |
|---|---|---|
| data | Object | An object mapping column names to data values to insert. |
| keyColumns | Array.<string> | The names of columns in the data object. If there is already a row in the table with the same values for these columns as the values being inserted, the data will not be inserted. |
| cb | queryCallback | A callback that gets called with the results of the query. |
Returns: ?Promise - If the cb parameter is omitted, a promise that will
resolve with the results of the query is returned.
Example: Insert a new user if a user with the same email does not exist
userTable.insertIfNotExists({email: 'email@example.com', name: 'John Doe'}, ['email'])
.then(result => result.affectedRows);
// 0 - If there was a row with `email` = 'email@example.com' (row not inserted)
// 1 - If there wasn't (row was inserted)
// INSERT INTO `user` (`email`, `name`)
// SELECT 'email@example.com', 'John Doe'
// FROM DUAL WHERE NOT EXISTS (
// SELECT 1 FROM `user`
// WHERE `email` = 'email@example.com' LIMIT 1
// );Example: Insert without escaping some values
const data = {
placeId: 'ChIJK2f-X1bxK4gRkB0jxyh7AwU',
type: 'city',
location: mysql.raw('POINT(-80.5204096, 43.4642578)'),
};
placeTable.insertIfNotExists(data, ['placeId', 'type'])
.then(result => result.affectedRows);
// 0 - If there was a row with the same `placeId` and `type` (row not inserted)
// 1 - If there wasn't (row was inserted)
// INSERT INTO `place` (`placeId`, `type`, `location`)
// SELECT 'ChIJK2f-X1bxK4gRkB0jxyh7AwU', 'city', POINT(-80.5204096, 43.4642578)
// FROM DUAL WHERE NOT EXISTS (
// SELECT 1 FROM `place`
// WHERE `placeId` = 'ChIJK2f-X1bxK4gRkB0jxyh7AwU' AND `type` = 'city' LIMIT 1
// );mySQLTable.update(data, sqlString, values, cb) ⇒ Promise
Updates data in the table.
Note: The data and sqlString arguments are individually
optional but at least one of them must be specified.
| Param | Type | Description |
|---|---|---|
| data | Object | An object of (column name)-(data value) pairs that define the new column values. |
| sqlString | string | SQL to be appended to the query after the SET data clause or immediately after SET if data is omitted. |
| values | Array | Values to replace the placeholders in sqlString (and/or data). |
| cb | queryCallback | A callback that gets called with the results of the query. |
Returns: ?Promise - If the cb parameter is omitted, a promise that will resolve with the results
of the query is returned.
Example: With both the data and sqlString arguments
userTable.update({email: 'updated@email.com'}, 'WHERE `id` = ?', [5])
.then(result => result.changedRows); // 1
// UPDATE `user` SET `email` = 'updated@email.com'
// WHERE `id` = 5;Example: With only the sqlString argument
userTable.update("`word` = CONCAT('prefix', `word`)");
// UPDATE `user` SET `word` = CONCAT('prefix', `word`);
userTable.update('`points` = `points` + ? WHERE `winner` = ?', [10, 1]);
// UPDATE `user` SET `points` = `points` + 10
// WHERE `winner` = 1;Example: With only the data argument (updates all rows)
userTable.update({points: 1000});
// UPDATE `user` SET `points` = 1000;
userTable.update({points: mysql.raw('`points` + 10')});
// UPDATE `user` SET `points` = `points` + 10;mySQLTable.delete(sqlString, values, cb) ⇒ Promise
Deletes data from the table.
| Param | Type | Description |
|---|---|---|
| sqlString | string | SQL to be appended to the query after the FROM table clause. |
| values | Array | Values to replace the placeholders in sqlString. |
| cb | queryCallback | A callback that gets called with the results of the query. |
Returns: ?Promise - If the cb parameter is omitted, a promise that will resolve with the results
of the query is returned.
Example: Delete specific rows
userTable.delete('WHERE `spammer` = 1')
.then(result => result.affectedRows); // The number of deleted spammers
// DELETE FROM `user` WHERE `spammer` = 1;Example: Delete all rows (you probably don't want to do this)
userTable.delete((err, result) => {
if (err) throw err;
// all rows deleted :(
});
// DELETE FROM `user`;mySQLTable.query() ⇒ Promise
Exactly the same as pool.pquery().
mySQLTable.transacting(trxn) ⇒ MySQLTable
Returns a new MySQLTable instance that will perform queries using the provided transaction connection.
| Param | Type | Description |
|---|---|---|
| trxn | Connection | The transaction connection that will be used to perform queries. |
Returns: MySQLTable - A new MySQLTable instance that will perform queries using the provided transaction
connection instead of the PoolPlus instance that was used to create the original instance.
See: pool.transaction()
Example:
const animalsTable = pool.defineTable('animals', schema);
const petsTable = pool.defineTable('pets', schema);
pool.transaction((trxn) => {
return animalsTable.transacting(trxn)
.insert({type: 'dog'})
.then(result =>
petsTable.transacting(trxn)
.insert({typeID: result.insertId, name: 'Rover'})
);
}).then(result => {
// result is the result of inserting "Rover" into the pets table
}).catch(err => {
// An error occurred during the transaction
});Migration Strategies
The possible migration strategies are as follows:
safe- default in a production environment (NODE_ENV === 'production')alter- default in a development environmentdrop
In addition to being the default in a production environment, the safe strategy is the only allowed strategy in production. This means that if alter or drop are used anywhere to configure connections or tables, they will be ignored and safe will be used instead. However, it is possible to override this behavior to allow the alter strategy in production by setting the allowAlterInProduction option to true in the Pool configuration.
safe
Only allows newly-defined tables to be created. Existing tables are never changed in any way.
alter
Specifies that newly-defined tables will be created, existing tables that are no longer defined will be dropped, and existing tables that have a different definition from what is found in the database will be migrated with minimal data-loss.
To rename table columns, the column's old name must be specified in the column definition with the .oldName('name') method. If it is not, the column will be dropped and all of the data that was in that column will be lost.
Note: It is up to you to understand how changes to an existing table might affect the data. For example, changing a DOUBLE column to a FLOAT will cause the precision of the value to be reduced so some significant digits may be lost (i.e. 1.123456789 would be reduced to 1.12346). Furthermore, some changes to tables cannot be done and will cause an error. An example of this would be adding a column with the NOT NULL attribute to a non-empty table without specifying a default value.
Known Migrations That Will Not Work
- Altering a column in a certain way when a different table references that column as a foreign key.
- Normally this isn't a problem if the column type is being changed (since you'd also need to change the column type in the referencing table and
mysql-pluscan handle this case), but if only the column in the first table needs to change (such as modifying it'sAUTO_INCREMENTvalue), the operation will fail because of the foreign key constraint. - Workaround 1: Manually remove the foreign key constraint from the referencing table (using SQL) before syncing.
- Workaround 2: Remove the foreign key definition from the referencing table schema (i.e. by commenting it out) before syncing the column change, then restore the foreign key definition and re-sync.
- Normally this isn't a problem if the column type is being changed (since you'd also need to change the column type in the referencing table and
drop
All defined tables will be dropped and recreated.
Defining Table Schemas
A schema is defined by a JavaScript object with certain properties. For mysql-plus, the schema properties can be broken down into four main types:
Columns
Columns are defined using the column property which is an object where the keys are column names and the values are column definitions of a certain type.
Example:
{
columns: {
id: pool.ColTypes.bigint().unsigned().notNull().primaryKey().autoIncrement(),
email: pool.ColTypes.varchar(255).notNull().unique(),
points: pool.ColTypes.int().unsigned().default(0),
}
}See the Column Types section for all possible column types and attributes that can be defined.
Primary Key
string | string[]
The table’s primary key can be defined with the primaryKey property.
{
columns: {
id: pool.ColTypes.int().unsigned().notNull(),
name: pool.ColTypes.varchar(255).notNull(),
},
primaryKey: 'id'
}An array can be used to define a multi-column primary key.
{
columns: {
id: pool.ColTypes.int().unsigned().notNull(),
name: pool.ColTypes.varchar(255).notNull(),
},
primaryKey: ['id', 'name']
}Primary keys for string columns may include a key prefix length.
{
columns: {
id: pool.ColTypes.varchar(100).unsigned().notNull(),
},
primaryKey: 'id(20)'
}Keys
Keys can be defined with the keys property, which is an array of KeyTypes:
{
columns: {
id: pool.ColTypes.int().unsigned().notNull(),
accountID: pool.ColTypes.int().unsigned().notNull(),
email: pool.ColTypes.varchar(255).notNull(),
location: pool.ColTypes.point().notNull(),
description: pool.ColTypes.text(),
},
keys: [
pool.KeyTypes.index('accountID'),
pool.KeyTypes.uniqueIndex('email'),
pool.KeyTypes.spatialIndex('location'),
pool.KeyTypes.fulltextIndex('description'),
pool.KeyTypes.foreignKey('accountID').references('account', 'id'),
]
}See the Key Types section for information on the different types of keys that can be defined.
Table Options
These schema properties configure table-level options. The options currently supported are as follows:
engine- Specify the storage engine for the table (such as InnoDB or MyISAM)autoIncrement- The initialAUTO_INCREMENTvalue for the tablecharset- Specify a default character set for the tablecollate- Specify a default collation for the tablecompression- The compression algorithm used for page level compression (MySQL 5.7 + InnoDB only)rowFormat- Defines the physical format in which the rows are stored
Example:
{
columns: {...},
engine: 'MyISAM',
autoIncrement: 5000000000
charset: 'utf8mb4',
collate: 'utf8mb4_unicode_520_ci',
compression: 'LZ4',
rowFormat: 'COMPACT',
}Note: After explicitly defining a table option in a schema, if you remove it from the schema and resync your table definitions, the table option will not change in the database. To go back to the default value for the table option, you'll need to explicitly define it on the schema and resync the table (or manually change it on the command line), and then you may remove it from the schema.
Column Types
mysql.ColTypes and pool.ColTypes both expose the following methods:
tinyint([m])smallint([m])mediumint([m])int([m])integer([m])- synonym forintbigint([m])float([m [, d]])double([m [, d]])decimal([m [, d]])dec([m [, d]])- synonym fordecimalnumeric([m [, d]])- synonym fordecimalfixed([m [, d]])- synonym fordecimalbit([m])bool()- synonym fortinyint(1)boolean()- synonym fortinyint(1)date()datetime([m])timestamp([m])time([m])year()char([m])varchar(m)text([m])tinytext()mediumtext()longtext()binary([m])varbinary(m)blob([m])tinyblob()mediumblob()longblob()enum(...values)set(...values)json()geometry()point()linestring()polygon()multipoint()multilinestring()multipolygon()geometrycollection()
All of these methods return a ColumnDefinition class.
ColumnDefinition
This class is what is used to define the column's attributes. These attributes can be set using the following methods:
notNull()- Adds theNOT NULLattributedefault(value)- Sets the column'sDEFAULTvalue- Examples:
.default('Hello')producesDEFAULT 'Hello'.default(null)producesDEFAULT NULL
- Note:
*blob,*text,json, and geometry columns cannot be assigned a default value other thannull.
- Examples:
primaryKey()- Declares the column to be the table's primary keyunique()- Creates a unique index for the columnindex()- Creates an index for the columnoldName(name: string)- The previous/current column name. If a column with this name exists, it will be renamed to the column name associated with the column defintion so that the data in that column will not be lost.
All ColumnDefinition methods return the ColumnDefinition, so they are chainable.
Additionally, certain column types have type-specific methods. These are as follows:
NumericColumnDefinition
Methods:
unsigned()- Adds theunsignedattributezerofill()- Adds thezerofillattributeautoIncrement()- Adds theAUTO_INCREMENTattribute
Compatible types:
tinyintsmallintmediumintintintegerbigintfloatdoubledecimaldecnumericfixed
TextColumnDefinition
Methods:
charset(value)- Sets the column's character setcollate(value)- Sets the column's collationfulltextIndex()- Creates a fulltext index for the column (excludingenumandsetcolumns)
Compatible types:
charvarchartexttinytextmediumtextlongtextenumset
UpdatableTimeColumnDefinition
Methods:
defaultCurrentTimestamp()- Adds theDEFAULT CURRENT_TIMESTAMPattributeonUpdateCurrentTimestamp()- Adds theON UPDATE CURRENT_TIMESTAMPattribute
Compatible types:
datetimetimestamp
TimestampColumnDefinition
Compatible types:
timestamp
There aren't any extra methods on this type, but there are some things to be aware of with timestamp columns:
NULL Timestamps
Normally, timestamp columns are NOT NULL by default, however, mysql-plus defines timestamp columns to be NULL by default to keep column definition semantics consistent. Therefore, the following column definition:
{
ts: ColTypes.timestamp(),
}would define a column with this SQL:
`ts` timestamp NULL DEFAULT NULLTimestamps' DEFAULT value
If a timestamp column is defined with the notNull() method, the column's DEFAULT value will be set to CURRENT_TIMESTAMP. So the following:
{
ts: ColTypes.timestamp().notNull(), // equivalent to `ColTypes.timestamp().notNull().defaultCurrentTimestamp()`
}would define a column with this SQL:
`ts` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMPNormally if the DEFAULT is unspecified, MySQL uses CURRENT_TIMESTAMP as the DEFAULT value of only the first timestamp column and '0000-00-00 00:00:00' for subsequent columns, but mysql-plus uses CURRENT_TIMESTAMP for all timestamp columns for consistency.
GeometryColumnDefinition
Methods:
spatialIndex()- Creates a spatial index for the column
Compatible types:
geometrypointlinestringpolygonmultipointmultilinestringmultipolygongeometrycollection
Key Types
mysql.KeyTypes and pool.KeyTypes both expose the following methods for defining table keys:
index(keyPart [, ...otherKeyParts])- Creates a regular indexuniqueIndex(keyPart [, ...otherKeyParts])- Creates a unique indexspatialIndex(columnName)- Creates a spatial indexfulltextIndex(columnName, [...otherColumns])- Creates a fulltext indexforeignKey(columnName [, ...otherColumns])- Creates a foreign key constraint
Example:
{
keys: [
pool.KeyTypes.index('accountID'),
pool.KeyTypes.uniqueIndex('email'),
pool.KeyTypes.spatialIndex('location'),
pool.KeyTypes.fulltextIndex('description'),
pool.KeyTypes.foreignKey('accountID').references('account', 'id'),
// Multi-column keys
pool.KeyTypes.uniqueIndex('accountID', 'email'),
pool.KeyTypes.foreignKey('userID', 'accountID').references('user', ['id', 'accountID']),
]
}All key types have a name method that can be used to customize the key’s name (helpful if you need to use an index hint in a query):
{
keys: [
pool.KeyTypes.index('accountID').name('account_key'),
pool.KeyTypes.uniqueIndex('email').name('email_key'),
pool.KeyTypes.spatialIndex('location').name('location_key'),
pool.KeyTypes.fulltextIndex('description').name('description_key'),
pool.KeyTypes.foreignKey('accountID').references('account', 'id').name('account_foreign_key'),
]
}Foreign Keys
Foreign keys have the following additional methods:
references(tableName, columns)- Sets the name of the reference table (string) and the referenced columns (string|Array<string>)onDelete(action)- Sets the foreign key’sON DELETEaction, whereactionis one of:RESTRICT,CASCADE,SET NULL,NO ACTIONonUpdate(action)- Sets the foreign key’sON UPDATEaction (with the same options asonDelete)cascade()- Short for:.onDelete('CASCADE').onUpdate('CASCADE')
Example:
{
columns: {
id: /* ... */,
uid: /* ... */,
userID: /* ... */,
thingOne: /* ... */,
thingTwo: /* ... */,
},
keys: [
KeyTypes.foreignKey('id').references('other_table', 'id'),
KeyTypes.foreignKey('uid').references('other_table', 'uid').cascade(),
KeyTypes.foreignKey('userID').references('user', 'id').onDelete('CASCADE').onUpdate('SET NULL'),
KeyTypes.foreignKey('thingOne', 'thingTwo').references('thing_table', ['one', 'two']),
]
}Note: Foreign keys don't define indexes, but constraints. When defining foreign keys, the columns used in the key should also have an index.
Indexes required for the example above:
{
primaryKey: 'id',
keys: [
KeyTypes.uniqueIndex('uid'),
KeyTypes.uniqueIndex('userID'),
KeyTypes.index('thingOne', 'thingTwo'),
]
}Prefix Lengths
PRIMARY, INDEX, and UNIQUE keys on char, varchar, binary, varbinary, blob, and text columns may include a key prefix length.
{
columns: {
id: ColTypes.char(50).notNull(),
uid: ColTypes.varchar(100).notNull(),
description: ColTypes.text(),
},
primaryKey: 'id(10)',
keys: [
KeyTypes.uniqueIndex('uid(30)'),
KeyTypes.index('description(50)'),
]5 years ago
6 years ago
6 years ago
7 years ago
8 years ago
8 years ago
8 years ago
8 years ago
8 years ago
8 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
9 years ago
10 years ago
10 years ago
10 years ago