CRUD

To interact with the database you need a Session object as this object holds the connection to the database. All CRUD operations are accessible via the session object and the generated models. The methods can be found under the static db field in your generated models.

For the following examples we will use this model:

class: Company
table: company
fields:
  name: String

note

You can also access the database methods through the session object under the field dbNext. However, this is typically only recommended if you want to do custom queries where you explicitly type out your SQL queries. The db field on Session contains legacy methods that are included for compatibility. In version 2 of Serverpod, the old legacy methods will be removed and db will be replaced by dbNext.

Create

There are two ways to create a new row in the database.

Inserting a single row

Inserting a single row to the database is done by calling the insertRow method on your generated model. The method will return the entire company object with the id field set.

var row = Company(name: 'Serverpod');
var company = await Company.db.insertRow(session, row);

Inserting several rows

Inserting several rows in a batch operation is done by calling the insert method. This is an atomic operation, meaning no entries will be created if any entry fails to be created.

var rows = [Company(name: 'Serverpod'), Company(name: 'Google')];
var companies = await Company.db.insert(session, rows);

info

In previous versions of Serverpod the insert method mutated the input object by setting the id field. In the example above the input variable remains unmodified after the insert/insertRow call.

Read

There are three different read operations available.

Finding by id

You can retrieve a single row by its id.

var company = await Company.db.findById(session, companyId);

This operation either returns the model or null.

Finding a single row

You can find a single row using an expression.

var company = await Company.db.findRow(
  session,
  where: (t) => t.name.equals('Serverpod'),
);

This operation returns the first model matching the filtering criteria or null. See filter and sort for all filter operations.

info

Note that ordering of the entries is important here as it will return the fist row returned by the database query.

Finding multiple rows

To find multiple rows, use the same principle as for finding a single row.

var companies = await Company.db.find(
  session,
  where: (t) => t.id < 100,
  limit: 50,
);

This operation returns a List of your models matching the filtering criteria.

See filter and sort for all filter and sorting operations and pagination for how to paginate the result.

Update

There are two update operations available.

Update a single row

To update a single row, use the updateRow method.

var company = await Company.db.findById(session, companyId); // Fetched company has its id set 
company.name = 'New name';
var updatedCompany = await Company.db.updateRow(session, company);

The object that you update must have its id set to a non-null value and the id needs to exist on a row in the database. The updateRow method returns the updated object.

Update several rows

To batch update several rows use the update method.

var companies = await Company.db.find(session);
companies = companies.map((c) => c.copyWith(name: 'New name')).toList();
var updatedCompanies = await Company.db.update(session, companies);

This is an atomic operation, meaning no entries will be updated if any entry fails to be updated. The update method returns a List of the updated objects.

Delete

Deleting rows from the database is done in a similar way to updating rows. However, there are three delete operations available.

Delete a single row

To delete a single row, use the deleteRow method.

var company = await Company.db.findById(session, companyId); // Fetched company has its id set 
var id = await Company.db.deleteRow(session, company);

The input object needs to have the id field set. The deleteRow method returns the id of the deleted row.

Delete several rows

To batch delete several rows, use the delete method.

var ids = await Company.db.delete(session, companies);

This is an atomic operation, meaning no entries will be deleted if any entry fails to be deleted. The delete method returns a List of the ids of the deleted row(s).

Delete by filter

You can also do a filtered delete and delete all entries matching a where query, by using the deleteWhere method.

var ids = await Company.db.deleteWhere(
  session,
  where: (t) => t.name.like('%Ltd'),
);

The above example will delete any row that ends in Ltd. The deleteWhere method returns a List of the ids of the deleted row(s).

Count

Count is a special type of query that helps counting the number of rows in the database that matches a specific filter.

var count = await Company.db.count(
  session, 
  where: (t) => t.name.like('s%'),
);

The return value is an int for the number of rows matching the filter.