表表示形式（表格）
在表格模型中，表是数据的基本表示形式。
表表示形式
AMO 中的表
使用 AMO 管理表时，不存在一对一的对象匹配。 在 AMO 中，表由 Dimension 和 MeasureGroup 表示。 为了提供度量值组，必须定义 Cube 来承载度量值组。 为了提供维度、度量值组和多维数据集，必须定义数据源视图对象来保存对数据源的绑定定义。
从过程角度来看，需要在定义任何其他对象之前先创建数据源视图。 数据源视图对象包含数据源中所有相关对象的映射。 关系模型的映射作为 .Net DataSet 对象嵌入数据源视图并存储在 DSV 的 Schema 属性中。
以下代码片段假定你有一个 SQL 客户端连接字符串，一个 Select 语句字典，这些语句映射到你打算在表格模型中表示的关系模型中的所有表，以及一个变量 newDataSourceViewName，其中包含数据源视图的名称 (通常与关系数据库) 的名称。
DataSet newDataSourceViewDataSet = new DataSet(newDataSourceViewName);
Foreach( String tableName in listOfSqlStatements.Keys)
{
String sqlStmt = listOfSqlStatements[tableName];
DataTable newTable = new DataTable(tableName);
using (SqlConnection SqlCnx = new SqlConnection(SqlCnxStr))
{
SqlDataAdapter dataAdapter = new SqlDataAdapter(sqlStmt, SqlCnx);
dataAdapter.FillSchema(newTable, SchemaType.Source);
}
newDataSourceViewDataSet.Tables.Add(newTable);
}
AMO.DataSourceView newDatasourceView = newDatabase.DataSourceViews.AddNew(newDataSourceViewName, newDataSourceViewName);
newDatasourceView.DataSourceID = newDatasource.ID; //This is the ID of the DataSource object
newDatasourceView.Schema = newDataSourceViewDataSet; //Here you are storing all the relational schema in the DSV
newDatasourceView.Update();
一旦创建并更新了数据源视图，就需要创建多维数据集对象，但直到创建第一个表后才能在服务器更新多维数据集对象。 多维数据集对象不能创建为空。 下面的代码段演示如何创建多维数据集；该代码段假定您具有非空字符串 newCubeName，而且该多维数据集的名称已经过验证，不与其他名称重名。
modelCube = newDatabase.Cubes.Add(newCubeName, newCubeName);
modelCube.Source = new AMO.DataSourceViewBinding(newDatasourceView.ID);
modelCube.StorageMode = AMO.StorageMode.InMemory;
modelCube.Language = newDatabase.Language;
modelCube.Collation = newDatabase.Collation;
//Create initial MdxScript
AMO.MdxScript mdxScript = modelCube.MdxScripts.Add("MdxScript", "MdxScript");
StringBuilder initialCommand = new StringBuilder();
initialCommand.AppendLine("CALCULATE;");
initialCommand.AppendLine("CREATE MEMBER CURRENTCUBE.Measures.[__No measures defined] AS 1;");
initialCommand.AppendLine("ALTER CUBE CURRENTCUBE UPDATE DIMENSION Measures, Default_Member = [__No measures defined];");
mdxScript.Commands.Add(new AMO.Command(initialCommand.ToString()));
一旦在本地定义了多维数据集，就可以创建和更新表。 以下过程概述了创建表所需的步骤：
创建表示表的维度，但不要更新服务器。
创建 RowNumber 属性，并将其定义为该维度的键属性。
创建维度属性，并将其标记为与 RowNumber 具有一对多关系。
向多维数据集维度添加维度。
创建同样表示该表的度量值组。
向度量值组添加维度。
在该度量值组中创建 AMO 默认度量值对象。 请注意，这是唯一一次需要使用 AMO 度量值对象；表格模型中的计算度量值在 AMO MdxScripts[“MdxScript”] 对象中定义。
创建默认分区。
更新数据库。
下面的代码段演示如何创建表：
private Boolean CreateTable(
AMO.Database db //the AMO database object where dimension are created
, AMO.Cube cb //the AMO cube where measure group is created
, DataTable dataTable //the schema of the table to be created
)
{
String tableID = dataTable.TableName;
if (db.Dimensions.Contains(tableID))
{
if (cb.MeasureGroups.Contains(tableID))
{
cb.MeasureGroups[tableID].Measures.Clear();
cb.MeasureGroups[tableID].Partitions.Clear();
cb.MeasureGroups.Remove(tableID, true);
}
if (cb.Dimensions.Contains(tableID))
{
cb.Dimensions.Remove(tableID, true);
}
db.Dimensions.Remove(tableID);
}
#region Create Dimension
//Define Dimension general properties
AMO.Dimension currentDimension = db.Dimensions.AddNew(tableID, tableID);
currentDimension.Source = new AMO.DataSourceViewBinding(newDatasourceView.ID);
currentDimension.StorageMode = AMO.DimensionStorageMode.InMemory;
currentDimension.UnknownMember = AMO.UnknownMemberBehavior.AutomaticNull;
currentDimension.UnknownMemberName = "Unknown";
currentDimension.ErrorConfiguration = new AMO.ErrorConfiguration();
currentDimension.ErrorConfiguration.KeyNotFound = AMO.ErrorOption.IgnoreError;
currentDimension.ErrorConfiguration.KeyDuplicate = AMO.ErrorOption.ReportAndStop;
currentDimension.ErrorConfiguration.NullKeyNotAllowed = AMO.ErrorOption.ReportAndStop;
currentDimension.Language = db.Language;
currentDimension.Collation = db.Collation;
currentDimension.ProactiveCaching = new AMO.ProactiveCaching();
TimeSpan defaultProactiveChachingTimeSpan = new TimeSpan(0, 0, -1);
currentDimension.ProactiveCaching.SilenceInterval = defaultProactiveChachingTimeSpan;
currentDimension.ProactiveCaching.Latency = defaultProactiveChachingTimeSpan;
currentDimension.ProactiveCaching.SilenceOverrideInterval = defaultProactiveChachingTimeSpan;
currentDimension.ProactiveCaching.ForceRebuildInterval = defaultProactiveChachingTimeSpan;
currentDimension.ProactiveCaching.Source = new AMO.ProactiveCachingInheritedBinding();
//Manualy add a "RowNumber" attribute as the key attribute of the dimension, until a primary key is defined
//"RowNumber" a required column for a tabular model and has to be of type AMO.AttributeType.RowNumber and binding AMO.RowNumberBinding.
//The name of the "RowNumber" attribute can be any name, as long as type and binding are correctly set
//By default, the MS client tools set the column name and column ID of the RowNumber attribute to "RowNumber"
//In this sample, to avoid problems, on any customer table that contains a column named 'RowNumber'
//the Id value of the column (in the dimension object) will be renamed to 'RowNumber_in_<TableName>' and the Name of the column will remain "RowNumber"
AMO.DimensionAttribute currentAttribute = currentDimension.Attributes.Add("RowNumber", "RowNumber");
currentAttribute.Type = AMO.AttributeType.RowNumber;
currentAttribute.KeyUniquenessGuarantee = true;
currentAttribute.Usage = AMO.AttributeUsage.Key;
currentAttribute.KeyColumns.Add(new AMO.DataItem());
currentAttribute.KeyColumns[0].DataType = System.Data.OleDb.OleDbType.Integer;
currentAttribute.KeyColumns[0].DataSize = 4;
currentAttribute.KeyColumns[0].NullProcessing = AMO.NullProcessing.Error;
currentAttribute.KeyColumns[0].Source = new AMO.RowNumberBinding();
currentAttribute.NameColumn = new AMO.DataItem();
currentAttribute.NameColumn.DataType = System.Data.OleDb.OleDbType.WChar;
currentAttribute.NameColumn.DataSize = 4;
currentAttribute.NameColumn.NullProcessing = AMO.NullProcessing.ZeroOrBlank;
currentAttribute.NameColumn.Source = new AMO.RowNumberBinding();
currentAttribute.OrderBy = AMO.OrderBy.Key;
currentAttribute.AttributeHierarchyVisible = false;
//Deferring AttributeRelationships until after adding each other attribute
//Add each column in the table as an attribute in the dimension
foreach (DataColumn dataColumn in dataTable.Columns)
{
string attributeID, attributeName;
if (dataColumn.ColumnName != "RowNumber")
{
attributeID = dataColumn.ColumnName;
}
else
{
attributeID = string.Format("RowNumber_in_{0}", dataTable.TableName);
}
attributeName = dataColumn.ColumnName;
currentAttribute = currentDimension.Attributes.Add(attributeName, attributeID);
currentAttribute.Usage = AMO.AttributeUsage.Regular;
currentAttribute.KeyUniquenessGuarantee = false;
currentAttribute.KeyColumns.Add(new AMO.DataItem(dataTable.TableName, dataColumn.ColumnName, AMO.OleDbTypeConverter.GetRestrictedOleDbType(dataColumn.DataType)));
currentAttribute.KeyColumns[0].Source = new AMO.ColumnBinding(dataTable.TableName, dataColumn.ColumnName);
currentAttribute.KeyColumns[0].NullProcessing = AMO.NullProcessing.Preserve;
currentAttribute.NameColumn = new AMO.DataItem(dataTable.TableName, dataColumn.ColumnName, System.Data.OleDb.OleDbType.WChar);
currentAttribute.NameColumn.Source = new AMO.ColumnBinding(dataTable.TableName, dataColumn.ColumnName);
currentAttribute.NameColumn.NullProcessing = AMO.NullProcessing.ZeroOrBlank;
currentAttribute.OrderBy = AMO.OrderBy.Key;
AMO.AttributeRelationship currentAttributeRelationship = currentDimension.Attributes["RowNumber"].AttributeRelationships.Add(currentAttribute.ID);
currentAttributeRelationship.Cardinality = AMO.Cardinality.Many;
currentAttributeRelationship.OverrideBehavior = AMO.OverrideBehavior.None;
}
#endregion
#region Add Dimension to Model cube
cb.Dimensions.Add(tableID, tableID, tableID);
#endregion
#region Add MeasureGroup to Model cube
AMO.MeasureGroup currentMeasureGroup = cb.MeasureGroups.Add(tableID, tableID);
currentMeasureGroup.StorageMode = AMO.StorageMode.InMemory;
currentMeasureGroup.ProcessingMode = AMO.ProcessingMode.Regular;
//Adding Dimension
AMO.DegenerateMeasureGroupDimension currentMGDim = new AMO.DegenerateMeasureGroupDimension(tableID);
currentMeasureGroup.Dimensions.Add(currentMGDim);
currentMGDim.ShareDimensionStorage = AMO.StorageSharingMode.Shared;
currentMGDim.CubeDimensionID = tableID;
foreach (AMO.CubeAttribute ca in cb.Dimensions[tableID].Attributes)
{
AMO.MeasureGroupAttribute mga = new AMO.MeasureGroupAttribute(ca.AttributeID);
if (mga.AttributeID == "RowNumber")
{
mga.Type = AMO.MeasureGroupAttributeType.Granularity;
AMO.DataItem rowNumberKeyColumn = new AMO.DataItem(new AMO.ColumnBinding(tableID, "RowNumber"));
rowNumberKeyColumn.DataType = System.Data.OleDb.OleDbType.Integer;
mga.KeyColumns.Add(rowNumberKeyColumn);
}
else
{
foreach (AMO.DataItem di in ca.Attribute.KeyColumns)
{
AMO.DataItem keyColumn = new AMO.DataItem(new AMO.ColumnBinding(tableID, ((AMO.ColumnBinding)di.Source).ColumnID));
keyColumn.DataType = di.DataType;
keyColumn.NullProcessing = AMO.NullProcessing.Preserve;
keyColumn.InvalidXmlCharacters = AMO.InvalidXmlCharacters.Remove;
mga.KeyColumns.Add(keyColumn);
}
}
currentMGDim.Attributes.Add(mga);
}
//Adding default Measure
String defaultMeasureID = string.Concat("_Count ", tableID);
AMO.Measure currentMeasure = currentMeasureGroup.Measures.Add(defaultMeasureID, defaultMeasureID);
currentMeasure.AggregateFunction = AMO.AggregationFunction.Count;
currentMeasure.DataType = AMO.MeasureDataType.BigInt;
AMO.DataItem currentMeasureSource = new AMO.DataItem(new AMO.RowBinding(tableID));
currentMeasureSource.DataType = System.Data.OleDb.OleDbType.BigInt;
currentMeasure.Source = currentMeasureSource;
//Partitions
AMO.Partition currentPartition = new AMO.Partition(tableID, tableID);
currentPartition.StorageMode = AMO.StorageMode.InMemory;
currentPartition.ProcessingMode = AMO.ProcessingMode.Regular;
currentPartition.Source = new AMO.QueryBinding(newDatasource.ID, (String)dataTable.ExtendedProperties["sqlStmt"]);
currentMeasureGroup.Partitions.Add(currentPartition);
#endregion
#region Update new objects in database
db.Update(AMO.UpdateOptions.ExpandFull, AMO.UpdateMode.UpdateOrCreate);
#endregion
return true;
}
注意
上面的代码段不具有出现错误时应具有的错误检查或清除过程。