drift library Null safety


Instruction to run a batched sql statement with the arguments provided.
The abstract base class for all select statements in the drift api. [...]
Contains operations to run queries in a batched mode. This can be much more efficient when running a lot of similar queries at the same time, making this api suitable for bulk updates.
Stores information needed to run batched statements in the order they were issued without preparing statements multiple times.
Maps Uint8List values from and to sql
A mapper for boolean values in sql. Booleans are represented as integers, where 0 means false and any other value means true.
Base class for columns in sql. Type T refers to the type a value of this column will have in Dart.
A column builder is used to specify which columns should appear in a table. All of the methods defined in this class and its subclasses are not meant to be called at runtime. Instead, the generator will take a look at your source code (specifically, it will analyze which of the methods you use) to figure out the column structure of a table.
A component is anything that can appear in a sql query.
An expression that represents the value of a dart object encoded to sql by writing them into the sql statements. For most cases, consider using Variable instead.
A custom expression that can appear in a sql statement. The CustomExpression.content will be written into the query without any modification. [...]
Base class for classes generated by custom queries in .drift files.
A select statement that is constructed with a raw sql prepared statement instead of the high-level drift api.
DatabaseAccessor<T extends GeneratedDatabase>
Class that runs queries to a subset of all available queries in a database. [...]
A database connection managed by drift. Contains three components: [...]
Manages a DatabaseConnection to send queries to the database.
Some abstract schema entity that can be stored in a database. This includes tables, triggers, views, indexes, etc.
A common supertype for all data classes generated by drift. Data classes are immutable structures that represent a single row in a database table.
A class to be used as an annotation on Table classes to customize the name for the data class that will be generated for the table class. The data class is a dart object that will be used to represent a row in the table. [...]
Maps DateTime values from and to sql
DeleteStatement<T extends Table, D>
A DELETE statement in sql
DoUpdate<T extends Table, D>
A DoUpdate upsert clause can be used to insert or update a custom companion when the underlying companion already exists. [...]
Annotation to use on classes that implement DatabaseAccessor. It specifies which tables should be made available in this dao. [...]
Use this class as an annotation to inform the generator that a database class should be generated using the specified DriftDatabase.tables. [...]
Defines additional runtime behavior for drift. Changing the fields of this class is rarely necessary.
An annotation specifying view properties
Implementation for an enum to int converter that uses the index of the enum as the value stored in the database.
Any sql expression that evaluates to some generic value. This does not include queries (which might evaluate to multiple values) but individual columns, functions and operators. [...]
A sql expression that calls a function. [...]
Base class for everything that can be used as a function parameter in sql. [...]
Information filled out by the generator to support generated or virtual columns.
Implementation for a Column declared on a table.
GeneratedColumnWithTypeConverter<D, S>
A GeneratedColumn with a type converter attached to it. [...]
A base class for all generated databases.
Contains information about a query while it's being constructed.
A "group by" clause in sql.
Base class for dsl Tables and Views.
A sqlite index on columns or expressions. [...]
Common interface for objects which can be inserted or updated into a database. D is the associated data class.
InsertStatement<T extends Table, D>
Represents an insert statement
Maps int values from and to sql
Join<T extends HasResultSet, D>
Used internally by drift when calling SimpleSelectStatement.join. [...]
JoinedSelectStatement<FirstT extends HasResultSet, FirstD>
A SELECT statement that operates on more than one table.
Annotation to use on column getters inside of a Table to define the name of the column in the json used by DataClass.toJson. [...]
A special database executor that delegates work to another QueryExecutor. The other executor is lazily opened by a DatabaseOpener.
A limit clause inside a select, update or delete statement.
Handles database migrations by delegating work to OnCreate and OnUpgrade methods.
Runs migrations declared by a MigrationStrategy.
A query executor for drift that delegates work to multiple executors.
Selectable methods for returning multiple results. [...]
NullAwareTypeConverter<D, S extends Object>
A type converter automatically mapping null values to null in both directions. [...]
An internal schema entity to run an sql statement when the database is created. [...]
Provides information about whether migrations ran before opening the database.
An order-by clause as part of a select statement. The clause can consist of multiple OrderingTerms, with the first terms being more important and the later terms only being considered if the first term considers two rows equal.
A single term in a OrderBy clause. The priority of this term is determined by its position in OrderBy.terms.
Used to order the precedence of sql expressions so that we can avoid unnecessary parens when generating sql statements.
Query<T extends HasResultSet, D>
Statement that operates with data that already exists (select, delete, update).
A query executor is responsible for executing statements on a database and return their results in a raw form. [...]
Callbacks passed to QueryExecutor.ensureOpen to run schema migrations when the database is first opened.
For custom select statements, represents a row in the result set.
An Insertable implementation based on raw column expressions. [...]
Maps double values from and to sql
ResultSetImplementation<Tbl, Row>
Interface for schema entities that have a result set. [...]
Abstract class for queries which can return one-time values or a stream of values. [...]
SimpleSelectStatement<T extends HasResultSet, D>
A select statement that doesn't use joins. [...]
Selectable methods for returning or streaming single, nullable results. [...]
Selectable methods for returning or streaming single, non-nullable results. [...]
A type that can be mapped from Dart to sql. The generic type parameter T denotes the resolved dart type.
Manages the set of SqlType known to a database. It's also responsible for returning the appropriate sql type for a given dart type.
Collects a set of UpdateRules which can be used to express how a set of direct updates to a table affects other updates. [...]
Mapper for string values in sql.
Subclasses represent a table in a database generated by drift. [...]
Contains instructions needed to run a complex migration on a table, using the steps described in Making other kinds of table schema changes. [...]
TableOrViewOperations<Tbl extends HasResultSet, Row>
A capture of a table and a generated database. [...]
Contains information on how a table was updated, which can be used to find queries that are affected by this.
A table update query describes information to listen for TableUpdates. [...]
A QueryExecutor that runs multiple queries atomically.
A sqlite trigger that's executed before, after or instead of a subset of writes on a specific tables. In drift, triggers can only be declared in .drift files. [...]
TypeConverter<D, S>
Maps a custom dart object of type D into a primitive type S understood by the sqlite backend. [...]
A result row in a JoinedSelectStatement that can parse the result of multiple entities.
A fixed-length list of 8-bit unsigned integers. [...]
An update companion for a DataClass which is used to write data into a database using InsertStatement.insert or UpdateStatement.write. [...]
A common rule that describes how a TableUpdate has other TableUpdates. [...]
UpdateStatement<T extends Table, D>
Represents an UPDATE statement in sql.
UpsertClause<T extends Table, D>
A upsert clause controls how to behave when a uniqueness constraint is violated during an insert. [...]
UpsertMultiple<T extends Table, D>
Upsert clause that consists of multiple clauses. [...]
An annotation specifying an existing class to be used as a data class.
A wrapper around arbitrary data T to indicate presence or absence explicitly. [...]
Serializer responsible for mapping atomic types from and to json.
An expression that represents the value of a dart object encoded to sql using prepared statements.
Used internally by drift for integrity checks.
Additional information that is passed to GeneratedColumns when verifying data to provide more helpful error messages.
Returned by GeneratedColumn.isAcceptableValue to provide a description when a valid is invalid.
Subclasses represent a view in a database generated by drift. [...]
ViewInfo<Self extends HasResultSet, Row>
A sqlite view. [...]
A column builder for virtual, generated columns. [...]
A where clause in a select, update or delete statement.
An UpdateRule for triggers that exist in a database. [...]


LimitContainerMixin<T extends HasResultSet, D>
Mixin to provide the high-level limit methods for users.
SingleTableQueryMixin<T extends HasResultSet, D>
Mixin for a Query that operates on a single primary table only.
TableInfo<TableDsl extends Table, D>
Base class for generated table classes. [...]
VirtualTableInfo<TableDsl extends Table, D>
Additional interface for tables in a drift file that have been created with an CREATE VIRTUAL TABLE STATEMENT.


Provides aggregate functions that are available for numeric expressions.
Defines the -, * and / operators on sql expressions that support it.
Provides aggregate functions that are available for each expression.
Defines operations on boolean values.
DSL extension to define a column inside a drift table.
Column builders available for both virtual and non-virtual columns.
Tells the generator to build an IntColumn. See the docs at ColumnBuilder for details.
Tells the generator to build an TextColumn. See the docs at ColumnBuilder for details.
Defines extension functions to express comparisons in sql
Provides aggregate functions that are available on date time expressions.
Provides expressions to extract information from date time values, or to calculate the difference between datetimes.
Extension providing the destructiveFallback strategy.
Extension to generate an alias for a table or a view.
Extension for generated dao classes to keep the old db field that was renamed to DatabaseAccessor.attachedDatabase in drift 3.0
Extension for statements on a table. [...]
Extension to use the rowid of a table in Dart queries.
Extension defines the isNull and isNotNull members to check whether the expression evaluates to null or not.
Defines methods that operate on a column storing String values.
Static extension members for generated table classes. [...]
Additional methods for a TableOrViewOperations that are only available on tables.


currentDate → const Expression<DateTime>
A sql expression that evaluates to the current date represented as a unix timestamp. The hour, minute and second fields will be set to 0.
_CustomDateTimeExpression("strftime('%s', CURRENT_DATE)")
currentDateAndTime → const Expression<DateTime>
A sql expression that evaluates to the current date and time, similar to DateTime.now. Timestamps are stored with a second accuracy.
_CustomDateTimeExpression("strftime('%s', CURRENT_TIMESTAMP)")
required → const Required
Used to annotate a named parameter p in a method or function f. Indicates that every invocation of f must include an argument corresponding to p, despite the fact that p would otherwise be an optional parameter. [...]


driftRuntimeOptions DriftRuntimeOptions
Stores the DriftRuntimeOptions describing global drift behavior across databases. [...]
read / write


coalesce<T>(List<Expression<T?>> expressions) Expression<T>
Evaluates to the first expression in expressions that's not null, or null if all expressions evaluate to null.
countAll({Expression<bool?>? filter}) Expression<int>
Returns the amount of rows in the current group matching the optional filter. [...]
crossJoin(Table other, {bool? useColumns}) Join<HasResultSet, dynamic>
Creates a sql cross join that can be used in SimpleSelectStatement.join. [...]
existsQuery(BaseSelectStatement select) Expression<bool>
The EXISTS operator checks whether the select subquery returns any rows.
innerJoin(Table other, Expression<bool?> on, {bool? useColumns}) Join<HasResultSet, dynamic>
Creates a sql inner join that can be used in SimpleSelectStatement.join. [...]
isNotNull(Expression inner) Expression<bool>
Expression that is true if the inner expression resolves to a non-null value.
@Deprecated('Use isNotNull through the SqlIsNull extension')
isNull(Expression inner) Expression<bool>
Expression that is true if the inner expression resolves to a null value.
@Deprecated('Use isNull through the SqlIsNull extension')
leftOuterJoin(Table other, Expression<bool?> on, {bool? useColumns}) Join<HasResultSet, dynamic>
Creates a sql left outer join that can be used in SimpleSelectStatement.join. [...]
notExistsQuery(BaseSelectStatement select) Expression<bool>
The NOT EXISTS operator evaluates to true if the select subquery does not return any rows.
subqueryExpression<R>(BaseSelectStatement statement) Expression<R>
Creates a subquery expression from the given statement. [...]


Builtin collating functions from sqlite. [...]
Enumeration of different insert behaviors. See the documentation on the individual fields for details.
A KeyAction can be used on a BuildColumn.references clause to describe how updates and deletes to a referenced table should propagate in your database. [...]
Describes how to order rows
An enumeration of database systems supported by drift. Only SqlDialect.sqlite is officially supported, all others are in an experimental state at the moment.
Classifies a TableUpdate by what kind of write happened - an insert, an update or a delete operation.


BlobColumn = Column<Uint8List?>
A column that stores arbitrary blobs of data as a Uint8List.
BoolColumn = Column<bool?>
A column that stores boolean values. Booleans will be stored as an integer that can either be 0 (false) or 1 (true).
DatabaseOpener = FutureOr<QueryExecutor> Function()
Signature of a function that opens a database connection when instructed to.
DateTimeColumn = Column<DateTime?>
A column that stores a DateTime. Times will be stored as unix timestamp and will thus have a second accuracy.
IntColumn = Column<int?>
A column that stores int values.
OnBeforeOpen = Future<void> Function(OpeningDetails details)
Signature of a function that's called before a database is marked opened by drift, but after migrations took place. This is a suitable callback to to populate initial data or issue PRAGMA statements that you want to use.
OnCreate = Future<void> Function(Migrator m)
Signature of a function that will be invoked when a database is created.
OnUpgrade = Future<void> Function(Migrator m, int from, int to)
Signature of a function that will be invoked when a database is upgraded or downgraded. In version upgrades: from < to In version downgrades: from > to
OrderClauseGenerator<T> = OrderingTerm Function(T tbl)
Signature of a function that generates an OrderingTerm when provided with a table.
RealColumn = Column<double?>
A column that stores floating point numeric values.
TextColumn = Column<String?>
A column that stores text.

Exceptions / Errors

Exception thrown by drift when rolling back a transaction fails. [...]
A wrapper class for internal exceptions thrown by the underlying database engine when drift can give additional context or help. [...]
Thrown when one attempts to insert or update invalid data into a table.