计算度量值表示形式 （表格）

计算度量值是每次使用 DAX 表达式时计算的命名 DAX 表达式。

计算度量值表示形式

AMO 中的计算度量值

使用 AMO 管理表格模型计算度量值时，逻辑计算度量值对象与对象对象MdxScript中Command定义的度量值之间存在一对一匹配。 每个 计算度量值 定义为 CREATE MEASURE 对象内的 Command 表达式，并用分号分隔。 表格模型中的所有计算度量值都对应于对象中一个MdxScript命令对象中的集合CREATE MEASURE字符串。 对于每个计算度量值，都有一对一映射与一个 CalculationProperty。

以下代码片段演示如何创建计算度量值。

  
private void addCalculatedMeasure(  
                   AMO.Cube modelCube  
                 , string cmTableName  
                 , string cmName  
                 , string newCalculatedMeasureExpression  
             )  
{  
    //Verify input requirements  
    if (string.IsNullOrEmpty(cmName) || string.IsNullOrWhiteSpace(cmName))  
    {  
        MessageBox.Show(String.Format("Calculated Measure name is not defined."), "AMO to Tabular message", MessageBoxButtons.OK, MessageBoxIcon.Error);  
        return;  
    }  
    if (string.IsNullOrEmpty(newCalculatedMeasureExpression) || string.IsNullOrWhiteSpace(newCalculatedMeasureExpression))  
    {  
        MessageBox.Show(String.Format("Calculated Measure expression is not defined."), "AMO to Tabular message", MessageBoxButtons.OK, MessageBoxIcon.Error);  
        return;  
    }  
  
    StringBuilder measuresCommand = new StringBuilder();  
  
    AMO.MdxScript mdxScript = modelCube.MdxScripts["MdxScript"];  
  
    //ToDo: Verify if measure already exits and ask user what wants to do next  
  
    if (mdxScript.Commands.Count == 1)  
    {  
        measuresCommand.AppendLine("-------------------------------------------------------------");  
        measuresCommand.AppendLine("-- Tabular Model measures command (do not modify manually) --");  
        measuresCommand.AppendLine("-------------------------------------------------------------");  
        measuresCommand.AppendLine();  
        measuresCommand.AppendLine();  
        mdxScript.Commands.Add(new AMO.Command(measuresCommand.ToString()));  
  
    }  
    else  
    {  
        measuresCommand.Append(mdxScript.Commands[1].Text);  
    }  
    measuresCommand.AppendLine(string.Format("CREATE MEASURE '{0}'[{1}]={2};", cmTableName, cmName, newCalculatedMeasureExpression));  
  
    mdxScript.Commands[1].Text = measuresCommand.ToString();  
  
    if (!mdxScript.CalculationProperties.Contains(cmName))  
    {  
        AMO.CalculationProperty cp = new AMO.CalculationProperty(cmName, AMO.CalculationType.Member);  
        cp.FormatString = ""; // ToDo: Get formatting attributes for the member  
        cp.Visible = true;  
        mdxScript.CalculationProperties.Add(cp);  
    }  
  
    try  
    {  
        modelCube.Update(AMO.UpdateOptions.ExpandFull, AMO.UpdateMode.UpdateOrCreate);  
        MessageBox.Show(String.Format("Calculated Measure successfully defined."), "AMO to Tabular message", MessageBoxButtons.OK, MessageBoxIcon.Information);  
    }  
    catch (AMO.OperationException amoOpXp)  
    {  
        MessageBox.Show(String.Format("Calculated Measure expression contains syntax errors, or references undefined or missspelled elements.\nError message: {0}", amoOpXp.Message), "AMO to Tabular message", MessageBoxButtons.OK, MessageBoxIcon.Warning);  
        return;  
    }  
    catch (AMO.AmoException amoXp)  
    {  
        MessageBox.Show(String.Format("AMO exception accessing the server.\nError message: {0}", amoXp.Message), "AMO to Tabular message", MessageBoxButtons.OK, MessageBoxIcon.Warning);  
        return;  
    }  
    catch (Exception)  
    {  
        throw;  
    }  
}