• Articolo

Metodo GetSchemaTable

Returns a DataTable that describes the column metadata of the AdomdDataReader.

Spazio dei nomi  Microsoft.AnalysisServices.AdomdClient
Assembly:  Microsoft.AnalysisServices.AdomdClient (in Microsoft.AnalysisServices.AdomdClient.dll)

Sintassi

'Dichiarazione
Public Function GetSchemaTable As DataTable
'Utilizzo
Dim instance As AdomdDataReader
Dim returnValue As DataTable

returnValue = instance.GetSchemaTable()

public DataTable GetSchemaTable()

public:
virtual DataTable^ GetSchemaTable() sealed

abstract GetSchemaTable : unit -> DataTable 
override GetSchemaTable : unit -> DataTable 

public final function GetSchemaTable() : DataTable

Valore restituito

Tipo: System.Data. . :: . .DataTable
A DataTable that contains the schema information for the current result of the AdomdDataReader.

Implementa

IDataReader. . :: . .GetSchemaTable() () () ()

Osservazioni

The following table describes the columns, in order, returned in the DataTable to present schema information about the current result.

Name

Data type

Description

ColumnName

String

The caption of the column; this might not be unique. If this cannot be determined, a null value is returned. This name always reflects the most recent renaming of the column in the current view or command text.

ColumnOrdinal

Int32

The ordinal number of the column. This is zero for the bookmark column of the row, if any. Other columns are numbered starting with one. This column cannot contain a null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value.

ColumnSize

Int32

This column always returns 0.

NumericPrecision

Int32

This column always returns 0.

NumericScale

Int32

This column always returns 0.

DataType

Type

Returns the Microsoft .NET Framework type of the column.

ProviderType

Object

The indicator of the column's data type. If the data type of the column varies from row to row, this must be Object. This column cannot contain a null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value.

IsLong

Boolean

Set if the column contains a Binary Long Object (BLOB) that contains very long data. The definition of very long data is provider-specific. The setting of this flag typically corresponds to the value of the IS_LONG column in the PROVIDER_TYPES rowset for the data type.

AllowDBNull

Boolean

Set if the consumer can set the column to a null value, or if the provider cannot determine whether or not the consumer can set the column to a null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value. Otherwise, not set. A column may contain null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). values, even if it cannot be set to a null value.

IsReadOnly

Boolean

Returns true if the column can be modified; otherwise false.

This column always returns true.

IsRowVersion

String

Set if the column contains a persistent row identifier that cannot be written to, and has no meaningful value except to identity the row.

IsUnique

Boolean

Returns true if no two rows in the base table (the table returned in BASETABLENAME) can have the same value in this column. IsUnique is guaranteed to be true if the column constitutes a key by itself or if there is a constraint of type UNIQUE that applies only to this column. Otherwise, this column returns false if the column can contain duplicate values in the base table. The default of this column is false.

IsKey

Boolean

Returns true if the column is one of a set of columns in the rowset that, taken together, uniquely identify the row. The set of columns with IsKey set to true must uniquely identify a row in the rowset. There is no requirement that this set of columns is a minimal set of columns. This set of columns may be generated from a base table primary key, a unique constraint or a unique index. Otherwise, returns false if the column is not required to uniquely identify the row.

This column always returns false.

IsAutoIncrement

Boolean

This column returns true if the column assigns values to new rows in fixed increments. Otherwise, this column returns false.

This column always returns false.

BaseSchemaName

String

The name of the schema in the data store that contains the column. A null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value if the base schema name cannot be determined.

This column always returns a null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value.

BaseCatalogName

String

The name of the catalog in the data store that contains the column. A null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value if the base catalog name cannot be determined.

This column always returns a null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value.

BaseTableName

String

The name of the table or view in the data store that contains the column. A null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value if the base table name cannot be determined.

This column always returns a null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value.

BaseColumnName

String

The name of the column in the result. This might be different than the column name returned in the ColumnName column if an alias was used. A null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value is returned if the base column name cannot be determined or if the rowset column is derived, but not identical to, a column in the result.

This column always returns a null Nothing nullptr unit riferimento Null (Nothing in Visual Basic). value.