MssqlExistsValue class
EXISTS (SELECT ...) as a value, for a projection rather than a WHERE.
SQL Server has no boolean expression: EXISTS is a predicate and a
predicate cannot be selected, so SELECT EXISTS (…) is a syntax error.
A CASE around it is the only way to project the answer, and the CAST
to bit is what makes the result decode as a Dart bool rather than as
the 1 or 0 the CASE produces.
Still EXISTS inside, not COUNT(*) > 0: the server stops at the first
matching row rather than counting all of them.
- Inheritance
-
- Object
- MssqlExpression
- MssqlExistsValue
- Implemented types
- Available extensions
- Annotations
-
- @immutable
Constructors
- MssqlExistsValue(MssqlSelectQuery query, {bool negated = false})
-
const
Properties
- hashCode → int
-
The hash code for this object.
no setterinherited
- negated → bool
-
final
- query → MssqlSelectQuery
-
final
- resultType → MssqlColumnType
-
bit, and never null: theCASEcovers both branches.no setteroverride - runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
as(
String alias) → MssqlAliased -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
Gives this expression a result alias. -
asc(
{MssqlNulls? nulls}) → MssqlOrder -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
Orders by this expression, ascending. -
between(
Object? lower, Object? upper) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
betweenColumns(
String lower, String upper) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
BETWEENtwo other columns rather than two values. -
compile(
MssqlParameterAllocator parameters, MssqlDialect dialect) → String -
Writes this expression's SQL, binding any values through
parameters.override -
desc(
{MssqlNulls? nulls}) → MssqlOrder -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
Orders by this expression, descending. -
eq(
Object? value) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
eqCol(
String identifier) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
Compares this expression to another column rather than to a value. -
eqExpr(
MssqlExpression other) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
Compares this expression to another expression. -
gt(
Object? value) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
gte(
Object? value) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
inList(
Iterable< Object?> values) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
inQuery(
MssqlSelectQuery query) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlSubqueryExpressionOperators extension
-
isNotNull(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
isNull(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
lt(
Object? value) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
lte(
Object? value) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
ne(
Object? value) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
notBetween(
Object? lower, Object? upper) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
notBetweenColumns(
String lower, String upper) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
notInList(
Iterable< Object?> values) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
notInQuery(
MssqlSelectQuery query) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlSubqueryExpressionOperators extension
-
toString(
) → String -
A string representation of this object.
inherited
-
whereAfterToday(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
whereBeforeToday(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
whereDate(
Object? value, [MssqlOperator operator = MssqlOperator.eq]) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
Compares the date alone, so the whole day matches rather than midnight. -
whereDay(
int value, [MssqlOperator operator = MssqlOperator.eq]) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
whereFuture(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
whereMonth(
int value, [MssqlOperator operator = MssqlOperator.eq]) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
whereNowOrFuture(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
whereNowOrPast(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
wherePast(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
Strictly earlier than now, again by the server's clock. -
whereTime(
Object? value, [MssqlOperator operator = MssqlOperator.eq]) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
Compares the time of day, with the date discarded. -
whereToday(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
The date part equals today, as the server reckons it. -
whereTodayOrAfter(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
whereTodayOrBefore(
) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
-
whereYear(
int value, [MssqlOperator operator = MssqlOperator.eq]) → MssqlCondition -
Available on MssqlExpression, provided by the MssqlExpressionOperators extension
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited