CASE Statement within a CASE

• michael.odonnell

  Grasshopper

  Points: 12

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  October 17, 2008 at 3:12 am

  #199652

  I have the following SQL statement:

  SELECT tbMeasurement.MonitoredEntityCode, CASE WHEN tbMeasurement.MonitoredLocationCode = 'EMISSION_POINT_1' THEN tbMeasurement.NumericResult END AS 'EMISSION_POINT_1'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'EMISSION_POINT_2' THEN tbMeasurement.NumericResult END AS 'EMISSION_POINT_2'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'EMISSION_POINT_3' THEN tbMeasurement.NumericResult END AS 'EMISSION_POINT_3'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'EMISSION_POINT_4' THEN tbMeasurement.NumericResult END AS 'EMISSION_POINT_4'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'EMISSION_POINT_5' THEN tbMeasurement.NumericResult END AS 'EMISSION_POINT_5'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'EMISSION_POINT_6' THEN tbMeasurement.NumericResult END AS 'EMISSION_POINT_6'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'EMISSION_POINT_7' THEN tbMeasurement.NumericResult END AS 'EMISSION_POINT_7'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'EMISSION_POINT_8' THEN tbMeasurement.NumericResult END AS 'EMISSION_POINT_8'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'EMISSION_POINT_9' THEN tbMeasurement.NumericResult END AS 'EMISSION_POINT_9'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'FUGITIVE_TOTAL' THEN tbMeasurement.NumericResult END AS 'FUGITIVE_TOTAL'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'ACCIDENTAL_TOTAL' THEN tbMeasurement.NumericResult END AS 'ACCIDENTAL TOTAL',

  tbMeasurement.SampleID, tbMeasurement.ParameterCode, tbParameter.ParameterDescription,

  tbMeasurementExtraData.M_C_E, tbMeasurementExtraData.MethodCode,

  tbMeasurementExtraData.Description

  FROM (tbMeasurement INNER JOIN

  tbParameter ON tbMeasurement.ParameterCode = tbParameter.ParameterCode) INNER JOIN

  tbMeasurementExtraData ON (tbMeasurement.ParameterCode = tbMeasurementExtraData.ParameterCode)

  AND (tbMeasurement.SampleID = tbMeasurementExtraData.SampleID)

  AND (tbMeasurement.MonitoredLocationCode = tbMeasurementExtraData.MonitoredLocationCode)

  AND (tbMeasurement.MonitoredEntityCode = tbMeasurementExtraData.MonitoredEntityCode)

  As you can see I as using a Case statement to create a new column for each type of emission point found and for Fugitive and Accidental Totals. What I am also trying to do is to replace the null values returned for Fugitive and Accidental Totals with a 0. I have tried using an inner case statement but that doesn't seem to work, any suggestions? I have also tried the replace statement, no effect.

  Michael.

• ChiragNS

  One Orange Chip

  Points: 26137

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  October 17, 2008 at 3:28 am

  #886239

  If i have understood correctly.........

  CASE WHEN tbMeasurement.MonitoredLocationCode = 'FUGITIVE_TOTAL' THEN ISNULL(tbMeasurement.NumericResult,0) END AS 'FUGITIVE_TOTAL'

  ,CASE WHEN tbMeasurement.MonitoredLocationCode = 'ACCIDENTAL_TOTAL' THEN ISNULL(tbMeasurement.NumericResult,0) END AS 'ACCIDENTAL TOTAL'

  "Keep Trying"

• ChrisM@Work

  SSC Guru

  Points: 186127

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  October 17, 2008 at 3:37 am

  #886240

  Using ISNULL?

  [font="Courier New"]SELECT m.MonitoredEntityCode,

     CASE WHEN m.MonitoredLocationCode = 'EMISSION_POINT_1' THEN m.NumericResult END AS 'EMISSION_POINT_1',

     CASE WHEN m.MonitoredLocationCode = 'EMISSION_POINT_2' THEN m.NumericResult END AS 'EMISSION_POINT_2',

     CASE WHEN m.MonitoredLocationCode = 'EMISSION_POINT_3' THEN m.NumericResult END AS 'EMISSION_POINT_3',

     CASE WHEN m.MonitoredLocationCode = 'EMISSION_POINT_4' THEN m.NumericResult END AS 'EMISSION_POINT_4',

     CASE WHEN m.MonitoredLocationCode = 'EMISSION_POINT_5' THEN m.NumericResult END AS 'EMISSION_POINT_5',

     CASE WHEN m.MonitoredLocationCode = 'EMISSION_POINT_6' THEN m.NumericResult END AS 'EMISSION_POINT_6',

     CASE WHEN m.MonitoredLocationCode = 'EMISSION_POINT_7' THEN m.NumericResult END AS 'EMISSION_POINT_7',

     CASE WHEN m.MonitoredLocationCode = 'EMISSION_POINT_8' THEN m.NumericResult END AS 'EMISSION_POINT_8',

     CASE WHEN m.MonitoredLocationCode = 'EMISSION_POINT_9' THEN m.NumericResult END AS 'EMISSION_POINT_9',

     CASE WHEN m.MonitoredLocationCode = 'FUGITIVE_TOTAL'   THEN ISNULL(m.NumericResult, 0) END AS 'FUGITIVE_TOTAL',

     CASE WHEN m.MonitoredLocationCode = 'ACCIDENTAL_TOTAL' THEN ISNULL(m.NumericResult, 0) END AS 'ACCIDENTAL TOTAL',

     m.SampleID, m.ParameterCode,

     p.ParameterDescription,

     e.M_C_E, e.MethodCode, e.Description

  FROM tbMeasurement m

  INNER JOIN tbParameter p ON m.ParameterCode = p.ParameterCode

  INNER JOIN tbMeasurementExtraData e ON m.ParameterCode = e.ParameterCode

     AND m.SampleID = e.SampleID

     AND m.MonitoredLocationCode = e.MonitoredLocationCode

     AND m.MonitoredEntityCode = e.MonitoredEntityCode

  [/font]

  Cheers

  ChrisM

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