SqlExpressionFactory.Coalesce 方法
定义
重要
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创建一个 SqlFunctionExpression 表示 COALESCE 操作的 。
public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlBinaryExpression Coalesce (Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression left, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression right, Microsoft.EntityFrameworkCore.Storage.RelationalTypeMapping typeMapping = default);
public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlFunctionExpression Coalesce (Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression left, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression right, Microsoft.EntityFrameworkCore.Storage.RelationalTypeMapping typeMapping = default);
public virtual Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlFunctionExpression Coalesce (Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression left, Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression right, Microsoft.EntityFrameworkCore.Storage.RelationalTypeMapping? typeMapping = default);
abstract member Coalesce : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Storage.RelationalTypeMapping -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlBinaryExpression
override this.Coalesce : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Storage.RelationalTypeMapping -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlBinaryExpression
abstract member Coalesce : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Storage.RelationalTypeMapping -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlFunctionExpression
override this.Coalesce : Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlExpression * Microsoft.EntityFrameworkCore.Storage.RelationalTypeMapping -> Microsoft.EntityFrameworkCore.Query.SqlExpressions.SqlFunctionExpression
Public Overridable Function Coalesce (left As SqlExpression, right As SqlExpression, Optional typeMapping As RelationalTypeMapping = Nothing) As SqlBinaryExpression
Public Overridable Function Coalesce (left As SqlExpression, right As SqlExpression, Optional typeMapping As RelationalTypeMapping = Nothing) As SqlFunctionExpression
参数
- left
- SqlExpression
左操作数。
- right
- SqlExpression
右操作数。
- typeMapping
- RelationalTypeMapping
要分配给所创建表达式的类型映射。
返回
表示 SQL COALESCE 操作的表达式。