@@ -20,10 +19,6 @@ Sequelize follows [SEMVER](http://semver.org). Supports Node v6 and above to use
New to Sequelize? Take a look at the [Tutorials and Guides](https://sequelize.org/master). You might also be interested in the [API Reference](https://sequelize.org/master/identifiers).
## v5 Release
You can find the upgrade guide and changelog [here](https://sequelize.org/master/manual/upgrade-to-v5.html).
## Table of Contents
-[Installation](#installation)
-[Documentation](#documentation)
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@@ -53,17 +48,16 @@ $ npm install --save tedious # Microsoft SQL Server
If you have security issues to report please refer to our [Responsible Disclosure Policy](./SECURITY.md) for more details.
Sequelize supports two ways of using transactions:
* One which will automatically commit or rollback the transaction based on the result of a promise chain and, (if enabled) pass the transaction to all calls within the callback
* And one which leaves committing, rolling back and passing the transaction to the user.
1.**Managed**, One which will automatically commit or rollback the transaction based on the result of a promise chain and, (if CLS enabled) pass the transaction to all calls within the callback
2.**Unmanaged**, One which leaves committing, rolling back and passing the transaction to the user
The key difference is that the managed transaction uses a callback that expects a promise to be returned to it while the unmanaged transaction returns a promise.
## Managed transaction (auto-callback)
Managed transactions handle committing or rolling back the transaction automagically. You start a managed transaction by passing a callback to `sequelize.transaction`.
Managed transactions handle committing or rolling back the transaction automatically. You start a managed transaction by passing a callback to `sequelize.transaction`.
Notice how the callback passed to `transaction` returns a promise chain, and does not explicitly call `t.commit()` nor `t.rollback()`. If all promises in the returned chain are resolved successfully the transaction is committed. If one or several of the promises are rejected, the transaction is rolled back.
In the examples above, the transaction is still manually passed, by passing `{ transaction: t }` as the second argument. To automatically pass the transaction to all queries you must install the [continuation local storage](https://github.com/othiym23/node-continuation-local-storage)(CLS) module and instantiate a namespace in your own code:
* @param {string} [options.type='DEFERRED'] See `Sequelize.Transaction.TYPES` for possible options. Sqlite only.
* @param {string} [options.isolationLevel] See `Sequelize.Transaction.ISOLATION_LEVELS` for possible options
* @param {string} [options.deferrable] Sets the constraints to be deferred or immediately checked. See `Sequelize.Deferrable`. PostgreSQL Only
* @param {Function} [options.logging=false] A function that gets executed while running the query to log the sql.
* @param {Function} [autoCallback] The callback is called with the transaction object, and should return a promise. If the promise is resolved, the transaction commits; if the promise rejects, the transaction rolls back
* Exposes the validator.js object, so you can extend it with custom validation functions. The validator is exposed both on the instance, and on the constructor.
