Index: Application/Ringtoets/src/Application.Ringtoets.Migration.Core/EmbeddedResources/Migration_17.1_17.2.sql
===================================================================
diff -u -r3f43829cbe42bb1b252bcd8bddd65ca18fd6663e -r887b6a1a6f5d36a9fb823744f79c3e612fc60404
--- Application/Ringtoets/src/Application.Ringtoets.Migration.Core/EmbeddedResources/Migration_17.1_17.2.sql	(.../Migration_17.1_17.2.sql)	(revision 3f43829cbe42bb1b252bcd8bddd65ca18fd6663e)
+++ Application/Ringtoets/src/Application.Ringtoets.Migration.Core/EmbeddedResources/Migration_17.1_17.2.sql	(.../Migration_17.1_17.2.sql)	(revision 887b6a1a6f5d36a9fb823744f79c3e612fc60404)
@@ -96,8 +96,8 @@
 	[ClosingStructuresFailureMechanismMetaEntityId],
 	[FailureMechanismEntityId],
 	[N2A],
-	CASE WHEN COUNT([ClosingStructureEntityId]) THEN "Onbekend" ELSE NULL END,
-	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "Onbekend" ELSE NULL END
+	CASE WHEN COUNT([ClosingStructureEntityId]) THEN "" ELSE NULL END,
+	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "" ELSE NULL END
 	FROM [SOURCEPROJECT].ClosingStructuresFailureMechanismMetaEntity
 	LEFT JOIN [SOURCEPROJECT].ClosingStructureEntity USING (FailureMechanismEntityId)
 	LEFT JOIN [SOURCEPROJECT].ForeshoreProfileEntity USING (FailureMechanismEntityId)
@@ -161,7 +161,7 @@
 	[GrassCoverErosionOutwardsFailureMechanismMetaEntityId],
 	[FailureMechanismEntityId],
 	[N],
-	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "Onbekend" ELSE NULL END
+	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "" ELSE NULL END
 	FROM [SOURCEPROJECT].GrassCoverErosionOutwardsFailureMechanismMetaEntity
 	LEFT JOIN [SOURCEPROJECT].ForeshoreProfileEntity USING (FailureMechanismEntityId)
 	GROUP BY FailureMechanismEntityID;
@@ -236,8 +236,8 @@
 	[HeightStructuresFailureMechanismMetaEntityId],
 	[FailureMechanismEntityId],
 	[N],
-	CASE WHEN COUNT([HeightStructureEntityId]) THEN "Onbekend" ELSE NULL END,
-	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "Onbekend" ELSE NULL END
+	CASE WHEN COUNT([HeightStructureEntityId]) THEN "" ELSE NULL END,
+	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "" ELSE NULL END
 	FROM [SOURCEPROJECT].HeightStructuresFailureMechanismMetaEntity
 	LEFT JOIN [SOURCEPROJECT].HeightStructureEntity USING (FailureMechanismEntityId)
 	LEFT JOIN [SOURCEPROJECT].ForeshoreProfileEntity USING (FailureMechanismEntityId)
@@ -396,8 +396,8 @@
 	[StrengthStabilityPointConstructionFailureMechanismMetaEntityId],
 	[FailureMechanismEntityId],
 	[N],
-	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "Onbekend" ELSE NULL END,
-	CASE WHEN COUNT([StabilityPointStructureEntityId]) THEN "Onbekend" ELSE NULL END
+	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "" ELSE NULL END,
+	CASE WHEN COUNT([StabilityPointStructureEntityId]) THEN "" ELSE NULL END
 	FROM [SOURCEPROJECT].StabilityPointStructuresFailureMechanismMetaEntity
 	LEFT JOIN [SOURCEPROJECT].ForeshoreProfileEntity USING (FailureMechanismEntityId)
 	LEFT JOIN [SOURCEPROJECT].StabilityPointStructureEntity USING (FailureMechanismEntityId)
@@ -412,7 +412,7 @@
 	[ForeshoreProfileCollectionSourcePath])
 SELECT 
 	[FailureMechanismEntityId],
-	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "Onbekend" ELSE NULL END
+	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "" ELSE NULL END
 	FROM [SOURCEPROJECT].FailureMechanismEntity
 	LEFT JOIN [SOURCEPROJECT].ForeshoreProfileEntity USING (FailureMechanismEntityID)
 	WHERE FailureMechanismType = 7
@@ -441,7 +441,7 @@
 	[ForeshoreProfileCollectionSourcePath])
 SELECT 
 	[FailureMechanismEntityId],
-	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "Onbekend" ELSE NULL END
+	CASE WHEN COUNT([ForeshoreProfileEntityId]) THEN "" ELSE NULL END
 	FROM [SOURCEPROJECT].FailureMechanismEntity
 	LEFT JOIN [SOURCEPROJECT].ForeshoreProfileEntity USING (FailureMechanismEntityID)
 	WHERE FailureMechanismType = 3
Index: Application/Ringtoets/src/Application.Ringtoets.Migration.Core/EmbeddedResources/Migration_5_17.1.sql
===================================================================
diff -u -r3f43829cbe42bb1b252bcd8bddd65ca18fd6663e -r887b6a1a6f5d36a9fb823744f79c3e612fc60404
--- Application/Ringtoets/src/Application.Ringtoets.Migration.Core/EmbeddedResources/Migration_5_17.1.sql	(.../Migration_5_17.1.sql)	(revision 3f43829cbe42bb1b252bcd8bddd65ca18fd6663e)
+++ Application/Ringtoets/src/Application.Ringtoets.Migration.Core/EmbeddedResources/Migration_5_17.1.sql	(.../Migration_5_17.1.sql)	(revision 887b6a1a6f5d36a9fb823744f79c3e612fc60404)
@@ -129,8 +129,10 @@
 	[GrassCoverErosionInwardsFailureMechanismMetaEntityId],
 	[FailureMechanismEntityId],
 	[N],
-	"Onbekend"
-	FROM [SOURCEPROJECT].GrassCoverErosionInwardsFailureMechanismMetaEntity;
+	CASE WHEN COUNT([DikeProfileEntityId]) THEN "" ELSE NULL END
+	FROM [SOURCEPROJECT].GrassCoverErosionInwardsFailureMechanismMetaEntity
+	LEFT JOIN [SOURCEPROJECT].DikeProfileEntity USING (FailureMechanismEntityId)
+	GROUP BY FailureMechanismEntityId;
 INSERT INTO GrassCoverErosionInwardsSectionResultEntity SELECT * FROM [SOURCEPROJECT].GrassCoverErosionInwardsSectionResultEntity;
 INSERT INTO GrassCoverErosionOutwardsFailureMechanismMetaEntity SELECT * FROM [SOURCEPROJECT].GrassCoverErosionOutwardsFailureMechanismMetaEntity;
 INSERT INTO GrassCoverErosionOutwardsHydraulicLocationEntity SELECT * FROM [SOURCEPROJECT].GrassCoverErosionOutwardsHydraulicLocationEntity;
@@ -159,9 +161,12 @@
 	[FailureMechanismEntityId],
 	[A],
 	[WaterVolumetricWeight], 
-	"Onbekend", 
-	"Onbekend" 
-	FROM [SOURCEPROJECT].PipingFailureMechanismMetaEntity;
+	CASE WHEN COUNT([StochasticSoilModelEntityId]) THEN "" ELSE NULL END,
+	CASE WHEN COUNT([SurfaceLineEntityId]) THEN "" ELSE NULL END
+	FROM [SOURCEPROJECT].PipingFailureMechanismMetaEntity
+	LEFT JOIN [SOURCEPROJECT].StochasticSoilModelEntity USING (FailureMechanismEntityId)
+	LEFT JOIN [SOURCEPROJECT].SurfaceLineEntity USING (FailureMechanismEntityId)
+	GROUP BY FailureMechanismEntityId;
 INSERT INTO PipingSectionResultEntity SELECT * FROM [SOURCEPROJECT].PipingSectionResultEntity;
 INSERT INTO PipingStructureSectionResultEntity SELECT * FROM [SOURCEPROJECT].PipingStructureSectionResultEntity;
 INSERT INTO ProjectEntity SELECT * FROM [SOURCEPROJECT].ProjectEntity;
Index: Application/Ringtoets/test/Application.Ringtoets.Storage.Test/IntegrationTests/MigrationTo171IntegrationTest.cs
===================================================================
diff -u -r3f43829cbe42bb1b252bcd8bddd65ca18fd6663e -r887b6a1a6f5d36a9fb823744f79c3e612fc60404
--- Application/Ringtoets/test/Application.Ringtoets.Storage.Test/IntegrationTests/MigrationTo171IntegrationTest.cs	(.../MigrationTo171IntegrationTest.cs)	(revision 3f43829cbe42bb1b252bcd8bddd65ca18fd6663e)
+++ Application/Ringtoets/test/Application.Ringtoets.Storage.Test/IntegrationTests/MigrationTo171IntegrationTest.cs	(.../MigrationTo171IntegrationTest.cs)	(revision 887b6a1a6f5d36a9fb823744f79c3e612fc60404)
@@ -306,7 +306,7 @@
             const string validateFailureMechanisms =
                 "SELECT COUNT() = 0 " +
                 "FROM [GrassCoverErosionInwardsFailureMechanismMetaEntity] " +
-                "WHERE [DikeProfileCollectionSourcePath] != \"Onbekend\";";
+                "WHERE [DikeProfileCollectionSourcePath] != \"\";";
             reader.AssertReturnedDataIsValid(validateFailureMechanisms);
 
             const string validateCalculations =
@@ -352,8 +352,8 @@
             const string validateFailureMechanisms =
                 "SELECT COUNT() = 0 " +
                 "FROM [PipingFailureMechanismMetaEntity] " +
-                "WHERE [StochasticSoilModelSourcePath] != \"Onbekend\"" +
-                "OR [SurfacelineSourcePath] != \"Onbekend\";";
+                "WHERE [StochasticSoilModelSourcePath] != \"\"" +
+                "OR [SurfacelineSourcePath] != \"\";";
             reader.AssertReturnedDataIsValid(validateFailureMechanisms);
 
             const string validateCalculationOutputs =