selectExpressions method
BaseSelectStatement<TypedResult>
selectExpressions()
inherited
Creates a select statement without a FROM clause selecting columns.
In SQL, select statements without a table will return a single row where
all the columns are evaluated. Of course, columns cannot refer to
columns from a table as these are unavailable without a FROM clause.
To run or watch the select statement, call Selectable.get or
Selectable.watch. Each returns a list of TypedResult rows, for which
a column can be read with TypedResult.read.
This example uses selectExpressions to query the current time set on the
database server:
final row = await selectExpressions([currentDateAndTime]).getSingle();
final databaseTime = row.read(currentDateAndTime)!;
Implementation
BaseSelectStatement<TypedResult> selectExpressions(
Iterable<Expression> columns) {
return SelectWithoutTables(this, columns);
}