Class PgUnnestExpression
- Assembly
- Npgsql.EntityFrameworkCore.PostgreSQL.dll
An expression that represents a PostgreSQL unnest function call in a SQL tree.
public class PgUnnestExpression : PgTableValuedFunctionExpression, IRelationalQuotableExpression, IPrintableExpression, ITableBasedExpression, IEquatable<PgTableValuedFunctionExpression>- Inheritance
-
PgUnnestExpression
- Implements
- Inherited Members
Remarks
This expression is just a PgTableValuedFunctionExpression, adding the ability to provide an explicit column name
for its output (SELECT * FROM unnest(array) AS f(foo)). This is necessary since when the column name isn't explicitly
specified, it is automatically identical to the table alias (f above); since the table alias may get uniquified by
EF, this would break queries.
See unnest for more information and examples.
This is an internal API that supports the Entity Framework Core infrastructure and not subject to the same compatibility standards as public APIs. It may be changed or removed without notice in any release. You should only use it directly in your code with extreme caution and knowing that doing so can result in application failures when updating to a new Entity Framework Core release.
Constructors
PgUnnestExpression(string, SqlExpression, string, bool)
This is an internal API that supports the Entity Framework Core infrastructure and not subject to the same compatibility standards as public APIs. It may be changed or removed without notice in any release. You should only use it directly in your code with extreme caution and knowing that doing so can result in application failures when updating to a new Entity Framework Core release.
public PgUnnestExpression(string alias, SqlExpression array, string columnName, bool withOrdinality = true)Parameters
aliasstringarraySqlExpressioncolumnNamestringwithOrdinalitybool
Properties
Array
The array to be un-nested into a table.
public virtual SqlExpression Array { get; }Property Value
Remarks
This is an internal API that supports the Entity Framework Core infrastructure and not subject to the same compatibility standards as public APIs. It may be changed or removed without notice in any release. You should only use it directly in your code with extreme caution and knowing that doing so can result in application failures when updating to a new Entity Framework Core release.
ColumnName
The name of the column to be projected out from the unnest call.
public virtual string ColumnName { get; }Property Value
Remarks
This is an internal API that supports the Entity Framework Core infrastructure and not subject to the same compatibility standards as public APIs. It may be changed or removed without notice in any release. You should only use it directly in your code with extreme caution and knowing that doing so can result in application failures when updating to a new Entity Framework Core release.
Methods
Clone(string?, ExpressionVisitor)
Creates a new object that is a copy of the current instance.
public override TableExpressionBase Clone(string? alias, ExpressionVisitor cloningExpressionVisitor)Parameters
aliasstringThe alias to be used by the cloned table.
cloningExpressionVisitorExpressionVisitorThe cloning expression for further visitation of nested nodes.
Returns
- TableExpressionBase
A new object that is a copy of this instance.
Update(SqlExpression)
Creates a new expression that is like this one, but using the supplied children. If all of the children are the same, it will return this expression.
public virtual PgUnnestExpression Update(SqlExpression array)Parameters
arraySqlExpressionThe Array property of the result.
Returns
- PgUnnestExpression
This expression if no children changed, or an expression with the updated children.
Update(IReadOnlyList<SqlExpression>)
This is an internal API that supports the Entity Framework Core infrastructure and not subject to the same compatibility standards as public APIs. It may be changed or removed without notice in any release. You should only use it directly in your code with extreme caution and knowing that doing so can result in application failures when updating to a new Entity Framework Core release.
public override PgUnnestExpression Update(IReadOnlyList<SqlExpression> arguments)Parameters
argumentsIReadOnlyList<SqlExpression>
Returns
VisitChildren(ExpressionVisitor)
Reduces the node and then calls the visitor delegate on the reduced expression. The method throws an exception if the node is not reducible.
protected override Expression VisitChildren(ExpressionVisitor visitor)Parameters
visitorExpressionVisitorAn instance of Func<T, TResult>.
Returns
- Expression
The expression being visited, or an expression which should replace it in the tree.
WithAlias(string)
Returns a copy of the current TableExpressionBase with the new provided alias.
public override PgUnnestExpression WithAlias(string newAlias)Parameters
newAliasstringThe alias to apply to the returned TableExpressionBase.
Returns
WithColumnInfos(IReadOnlyList<ColumnInfo>)
This is an internal API that supports the Entity Framework Core infrastructure and not subject to the same compatibility standards as public APIs. It may be changed or removed without notice in any release. You should only use it directly in your code with extreme caution and knowing that doing so can result in application failures when updating to a new Entity Framework Core release.
public override PgUnnestExpression WithColumnInfos(IReadOnlyList<PgTableValuedFunctionExpression.ColumnInfo> columnInfos)Parameters
columnInfosIReadOnlyList<PgTableValuedFunctionExpression.ColumnInfo>