diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/aliases.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/aliases.test.ts
index 8ce40d503b..3050cee4c9 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/aliases.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/aliases.test.ts
@@ -17,7 +17,7 @@ import { buildTransform, TransformTable } from '../../../reportBuilder/transform
 describe('aliases', () => {
   it('keyValueByDataElementName', () => {
     const transform = buildTransform(['keyValueByDataElementName']);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', BCD1: 4 },
         { period: '20200102', organisationUnit: 'TO', BCD1: 2 },
@@ -28,7 +28,7 @@ describe('aliases', () => {
 
   it('keyValueByOrgUnit', () => {
     const transform = buildTransform(['keyValueByOrgUnit']);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', dataElement: 'BCD1', TO: 4 },
         { period: '20200102', dataElement: 'BCD1', TO: 2 },
@@ -39,7 +39,7 @@ describe('aliases', () => {
 
   it('keyValueByPeriod', () => {
     const transform = buildTransform(['keyValueByPeriod']);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows(
         [
           { organisationUnit: 'TO', dataElement: 'BCD1', '20200101': 4 },
@@ -53,7 +53,7 @@ describe('aliases', () => {
 
   it('mostRecentValuePerOrgUnit', () => {
     const transform = buildTransform(['mostRecentValuePerOrgUnit']);
-    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200103', organisationUnit: 'TO', BCD1: 5, BCD2: 0 },
         { period: '20200103', organisationUnit: 'PG', BCD1: 2, BCD2: -1 },
@@ -63,7 +63,7 @@ describe('aliases', () => {
 
   it('firstValuePerPeriodPerOrgUnit', () => {
     const transform = buildTransform(['firstValuePerPeriodPerOrgUnit']);
-    expect(transform(TransformTable.fromRows(MULTIPLE_MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', BCD1: 4, BCD2: 11 },
         { period: '20200102', organisationUnit: 'TO', BCD1: 2, BCD2: 1 },
@@ -77,7 +77,7 @@ describe('aliases', () => {
 
   it('lastValuePerPeriodPerOrgUnit', () => {
     const transform = buildTransform(['lastValuePerPeriodPerOrgUnit']);
-    expect(transform(TransformTable.fromRows(MULTIPLE_MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', BCD1: 7, BCD2: 4 },
         { period: '20200102', organisationUnit: 'TO', BCD1: 12, BCD2: 18 },
@@ -91,14 +91,14 @@ describe('aliases', () => {
 
   it('convertPeriodToWeek', () => {
     const transform = buildTransform(['convertPeriodToWeek']);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0], period: '2020W01' }]),
     );
   });
 
   it('convertEventDateToWeek', () => {
     const transform = buildTransform(['convertEventDateToWeek']);
-    expect(transform(TransformTable.fromRows(SINGLE_EVENT))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_EVENT))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_EVENT[0], period: '2020W01' }]),
     );
   });
@@ -107,7 +107,7 @@ describe('aliases', () => {
     const transform = buildTransform(['insertNumberOfFacilitiesColumn'], {
       facilityCountByOrgUnit: { TO: 14 },
     });
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0], numberOfFacilities: 14 }]),
     );
   });
@@ -116,7 +116,7 @@ describe('aliases', () => {
 describe('insertSummaryRowAndColumn', () => {
   it('inserts a summary row and summary column', () => {
     const transform = buildTransform(['insertSummaryRowAndColumn']);
-    expect(transform(TransformTable.fromRows(TRANSFORMED_SUMMARY_BINARY))).toEqual(
+    expect(transform(TransformTable.fromRows(TRANSFORMED_SUMMARY_BINARY))).toStrictEqual(
       TransformTable.fromRows([
         { dataElement: 'Male condoms', TO: 'N', FJ: 'N', NR: 'Y', KI: 'N', summaryColumn: '75.0%' },
         {
@@ -140,7 +140,7 @@ describe('insertSummaryRowAndColumn', () => {
 
   it('only summarises columns that have only Y | N | undefined values', () => {
     const transform = buildTransform(['insertSummaryRowAndColumn']);
-    expect(transform(TransformTable.fromRows(TRANSFORMED_SUMMARY_VARIOUS))).toEqual(
+    expect(transform(TransformTable.fromRows(TRANSFORMED_SUMMARY_VARIOUS))).toStrictEqual(
       TransformTable.fromRows([
         {
           dataElement: 'Male condoms',
diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/excludeColumns.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/excludeColumns.test.ts
index f5e1bd106c..be1d33c0fc 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/excludeColumns.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/excludeColumns.test.ts
@@ -14,7 +14,7 @@ describe('excludeColumns', () => {
         columns: '*',
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{}]),
     );
   });
@@ -26,7 +26,7 @@ describe('excludeColumns', () => {
         columns: ['organisationUnit', 'value'],
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', dataElement: 'BCD1' },
         { period: '20200102', dataElement: 'BCD1' },
diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/excludeRows.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/excludeRows.test.ts
index 038c58a08c..3d55871373 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/excludeRows.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/excludeRows.test.ts
@@ -14,7 +14,7 @@ describe('excludeRows', () => {
         where: '=$BCD1 < 6',
       },
     ]);
-    expect(transform(TransformTable.fromRows(EXCLUDEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(EXCLUDEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'PG', BCD1: 7 },
         { period: '20200102', organisationUnit: 'PG', BCD1: 8 },
diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/gatherColumns.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/gatherColumns.test.ts
index b9639f59f6..c6d78995ec 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/gatherColumns.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/gatherColumns.test.ts
@@ -13,7 +13,7 @@ describe('gatherColumns', () => {
         transform: 'gatherColumns',
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([
         { value: '20200101', columnName: 'period' },
         { value: 'TO', columnName: 'organisationUnit' },
@@ -30,7 +30,7 @@ describe('gatherColumns', () => {
         keep: 'organisationUnit',
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([
         { organisationUnit: 'TO', value: '20200101', columnName: 'period' },
         { organisationUnit: 'TO', value: 'BCD1', columnName: 'dataElement' },
@@ -46,7 +46,7 @@ describe('gatherColumns', () => {
         keep: ['organisationUnit', 'period'],
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', value: 'BCD1', columnName: 'dataElement' },
         { period: '20200101', organisationUnit: 'TO', value: 4, columnName: 'value' },
@@ -61,7 +61,7 @@ describe('gatherColumns', () => {
         keep: ['period'],
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', value: 'TO', columnName: 'organisationUnit' },
         { period: '20200101', value: 'BCD1', columnName: 'dataElement' },
diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/insertColumns.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/insertColumns.test.ts
index 385806d686..c865cf38e0 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/insertColumns.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/insertColumns.test.ts
@@ -18,7 +18,7 @@ describe('insertColumns', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0], number: 1, string: 'Hi', boolean: false }]),
     );
   });
@@ -32,7 +32,7 @@ describe('insertColumns', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0], dataElementValue: 4 }]),
     );
   });
@@ -46,7 +46,7 @@ describe('insertColumns', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0], BCD1: 4 }]),
     );
   });
@@ -60,7 +60,7 @@ describe('insertColumns', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0], period: '1st Jan 2020' }]),
     );
   });
@@ -75,7 +75,7 @@ describe('insertColumns', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { ...MULTIPLE_ANALYTICS[0], period: '1st Jan 2020', BCD1: 4 },
         { ...MULTIPLE_ANALYTICS[1], period: '2nd Jan 2020', BCD1: 2 },
@@ -94,7 +94,7 @@ describe('insertColumns', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows(
         [
           { ...MERGEABLE_ANALYTICS[0], newVal: 8 },
diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/insertRows.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/insertRows.test.ts
index f3386367ef..12e5ad01b4 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/insertRows.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/insertRows.test.ts
@@ -19,7 +19,7 @@ describe('insertRows', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([...SINGLE_ANALYTIC, { number: 1, string: 'Hi', boolean: false }]),
     );
   });
@@ -33,7 +33,7 @@ describe('insertRows', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([...SINGLE_ANALYTIC, { dataElementValue: 4 }]),
     );
   });
@@ -47,7 +47,7 @@ describe('insertRows', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([...SINGLE_ANALYTIC, { BCD1: 4 }]),
     );
   });
@@ -61,7 +61,7 @@ describe('insertRows', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([...SINGLE_ANALYTIC, { period: '1st Jan 2020' }]),
     );
   });
@@ -80,7 +80,7 @@ describe('insertRows', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows(
         [
           { number: 1, string: 'Hi', boolean: false },
@@ -105,7 +105,7 @@ describe('insertRows', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', dataElement: 'BCD1', value: 4 },
         { period: '20200102', organisationUnit: 'TO', dataElement: 'BCD1', value: 2 },
@@ -124,7 +124,7 @@ describe('insertRows', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', dataElement: 'BCD1', value: 4 },
         { dataElementValue: 4 },
@@ -146,7 +146,7 @@ describe('insertRows', () => {
         position: 'before',
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows(
         [
           { dataElementValue: 4 },
@@ -171,7 +171,7 @@ describe('insertRows', () => {
         position: 'start',
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows(
         [
           { dataElementValue: 4 },
@@ -197,7 +197,7 @@ describe('insertRows', () => {
         where: "=not(eq($period, '20200101'))",
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', dataElement: 'BCD1', value: 4 },
         { period: '20200102', organisationUnit: 'TO', dataElement: 'BCD1', value: 2 },
@@ -219,7 +219,7 @@ describe('insertRows', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', dataElement: 'BCD1', value: 4 },
         { period: '20200102', organisationUnit: 'TO', dataElement: 'BCD1', value: 2 },
@@ -242,7 +242,7 @@ describe('insertRows', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', BCD1: 4 },
         { period: '20200102', organisationUnit: 'TO', BCD1: 2 },
diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/mergeRows.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/mergeRows.test.ts
index 8f390b4b77..407bc95249 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/mergeRows.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/mergeRows.test.ts
@@ -30,7 +30,7 @@ describe('mergeRows', () => {
         groupBy: 'period',
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([{ period: '20200101', BCD1: 4, BCD2: 4, BCD3: 4 }]),
     );
   });
@@ -40,15 +40,15 @@ describe('mergeRows', () => {
       {
         transform: 'mergeRows',
         using: {
-          organisationUnit: 'exclude',
-          period: 'exclude',
+          organisationUnit: 'first',
+          period: 'first',
           '*': 'sum',
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
-        { period: undefined, organisationUnit: undefined, BCD1: 28, BCD2: 123 },
+        { period: '20200101', organisationUnit: 'TO', BCD1: 28, BCD2: 123 },
       ]),
     );
   });
@@ -61,7 +61,7 @@ describe('mergeRows', () => {
         using: 'last',
       },
     ]);
-    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200103', organisationUnit: 'TO', BCD1: 5, BCD2: 0 },
         { period: '20200103', organisationUnit: 'PG', BCD1: 2, BCD2: -1 },
@@ -77,7 +77,7 @@ describe('mergeRows', () => {
         using: 'sum',
       },
     ]);
-    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', BCD1: 4, BCD2: 11 },
         { period: '20200102', organisationUnit: 'TO', BCD1: 2, BCD2: 1 },
@@ -101,7 +101,7 @@ describe('mergeRows', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200103', organisationUnit: 'TO', BCD1: 11, BCD2: 0 },
         { period: '20200103', organisationUnit: 'PG', BCD1: 17, BCD2: -1 },
@@ -116,15 +116,15 @@ describe('mergeRows', () => {
           transform: 'mergeRows',
           groupBy: 'organisationUnit',
           using: {
-            period: 'exclude',
+            period: 'first',
             '*': 'sum',
           },
         },
       ]);
-      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
-          { period: undefined, organisationUnit: 'TO', BCD1: 11, BCD2: 12 },
-          { period: undefined, organisationUnit: 'PG', BCD1: 17, BCD2: 111 },
+          { period: '20200101', organisationUnit: 'TO', BCD1: 11, BCD2: 12 },
+          { period: '20200101', organisationUnit: 'PG', BCD1: 17, BCD2: 111 },
         ]),
       );
     });
@@ -135,7 +135,7 @@ describe('mergeRows', () => {
           transform: 'mergeRows',
           groupBy: 'organisationUnit',
           using: {
-            period: 'exclude',
+            period: 'first',
             '*': 'sum',
           },
         },
@@ -147,10 +147,10 @@ describe('mergeRows', () => {
             ...MERGEABLE_ANALYTICS_WITH_NULL_VALUES,
           ]),
         ),
-      ).toEqual(
+      ).toStrictEqual(
         TransformTable.fromRows([
-          { period: undefined, organisationUnit: 'TO', BCD1: 11, BCD2: 12 },
-          { period: undefined, organisationUnit: 'PG', BCD1: 17, BCD2: 111 },
+          { period: '20200101', organisationUnit: 'TO', BCD1: 11, BCD2: 12 },
+          { period: '20200101', organisationUnit: 'PG', BCD1: 17, BCD2: 111 },
         ]),
       );
     });
@@ -161,15 +161,15 @@ describe('mergeRows', () => {
           transform: 'mergeRows',
           groupBy: 'organisationUnit',
           using: {
-            period: 'exclude',
+            period: 'first',
             '*': 'average',
           },
         },
       ]);
-      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
-          { period: undefined, organisationUnit: 'TO', BCD1: 3.6666666666666665, BCD2: 4 },
-          { period: undefined, organisationUnit: 'PG', BCD1: 5.666666666666667, BCD2: 37 },
+          { period: '20200101', organisationUnit: 'TO', BCD1: 3.6666666666666665, BCD2: 4 },
+          { period: '20200101', organisationUnit: 'PG', BCD1: 5.666666666666667, BCD2: 37 },
         ]),
       );
     });
@@ -182,7 +182,7 @@ describe('mergeRows', () => {
           using: 'count',
         },
       ]);
-      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
           { period: '20200101', organisationUnit: 4, BCD1: 2, BCD2: 2 },
           { period: '20200102', organisationUnit: 4, BCD1: 2, BCD2: 2 },
@@ -199,7 +199,7 @@ describe('mergeRows', () => {
           using: 'max',
         },
       ]);
-      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
           { period: '20200103', organisationUnit: 'TO', BCD1: 5, BCD2: 11 },
           { period: '20200103', organisationUnit: 'PG', BCD1: 8, BCD2: 99 },
@@ -215,7 +215,7 @@ describe('mergeRows', () => {
           using: 'min',
         },
       ]);
-      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
           { period: '20200101', organisationUnit: 'PG', BCD1: 4, BCD2: 11 },
           { period: '20200102', organisationUnit: 'PG', BCD1: 2, BCD2: 1 },
@@ -239,7 +239,7 @@ describe('mergeRows', () => {
             ...MERGEABLE_ANALYTICS_WITH_NULL_VALUES,
           ]),
         ),
-      ).toEqual(
+      ).toStrictEqual(
         TransformTable.fromRows([
           { period: '20200101', organisationUnit: 'PG', BCD1: null, BCD2: null },
           { period: '20200102', organisationUnit: 'PG', BCD1: 2, BCD2: 1 },
@@ -256,7 +256,7 @@ describe('mergeRows', () => {
           using: 'unique',
         },
       ]);
-      expect(transform(TransformTable.fromRows(UNIQUE_MERGEABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(UNIQUE_MERGEABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
           {
             period: 'NO_UNIQUE_VALUE',
@@ -282,12 +282,11 @@ describe('mergeRows', () => {
           using: 'exclude',
         },
       ]);
-      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
-        TransformTable.fromRows([
-          { period: '20200101', organisationUnit: undefined, BCD1: undefined, BCD2: undefined },
-          { period: '20200102', organisationUnit: undefined, BCD1: undefined, BCD2: undefined },
-          { period: '20200103', organisationUnit: undefined, BCD1: undefined, BCD2: undefined },
-        ]),
+      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
+        TransformTable.fromRows(
+          [{ period: '20200101' }, { period: '20200102' }, { period: '20200103' }],
+          ['period', 'organisationUnit', 'BCD1', 'BCD2'], // excludes values, but keeps columns
+        ),
       );
     });
 
@@ -299,7 +298,7 @@ describe('mergeRows', () => {
           using: 'first',
         },
       ]);
-      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
           { period: '20200101', organisationUnit: 'TO', BCD1: 4, BCD2: 11 },
           { period: '20200101', organisationUnit: 'PG', BCD1: 7, BCD2: 13 },
@@ -315,7 +314,7 @@ describe('mergeRows', () => {
           using: 'last',
         },
       ]);
-      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
           { period: '20200101', organisationUnit: 'PG', BCD1: 7, BCD2: 13 },
           { period: '20200102', organisationUnit: 'PG', BCD1: 8, BCD2: 99 },
@@ -344,7 +343,7 @@ describe('mergeRows', () => {
             using: 'single',
           },
         ]);
-        expect(transform(TransformTable.fromRows(SINGLE_MERGEABLE_ANALYTICS))).toEqual(
+        expect(transform(TransformTable.fromRows(SINGLE_MERGEABLE_ANALYTICS))).toStrictEqual(
           TransformTable.fromRows([{ period: '20200101', BCD1: 4, BCD2: 4, BCD3: 4 }]),
         );
       });
diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/parser/parser.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/parser/parser.test.ts
index e8de2a0d0a..3e7f9dfacc 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/parser/parser.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/parser/parser.test.ts
@@ -30,80 +30,93 @@ describe('parser', () => {
       ],
       { query: { animal: 'cat' } },
     );
-    expect(transform(TransformTable.fromRows(PARSABLE_ANALYTICS))).toEqual(
-      TransformTable.fromRows([
-        {
-          variable: 4,
-          current: 4,
-          index: 1,
-          previous: undefined,
-          next: 2,
-          lastAll: 2,
-          sumAllPrevious: 4,
-          sumWhereMatchingOrgUnit: 11,
-          tableLength: 6,
-          requestParam: 'cat',
-        },
-        {
-          variable: 2,
-          current: 2,
-          index: 2,
-          previous: 4,
-          next: 5,
-          lastAll: 2,
-          sumAllPrevious: 6,
-          sumWhereMatchingOrgUnit: 11,
-          tableLength: 6,
-          requestParam: 'cat',
-        },
-        {
-          variable: 5,
-          current: 5,
-          index: 3,
-          previous: 2,
-          next: 7,
-          lastAll: 2,
-          sumAllPrevious: 11,
-          sumWhereMatchingOrgUnit: 11,
-          tableLength: 6,
-          requestParam: 'cat',
-        },
-        {
-          variable: 7,
-          current: 7,
-          index: 4,
-          previous: 5,
-          next: 8,
-          lastAll: 2,
-          sumAllPrevious: 18,
-          sumWhereMatchingOrgUnit: 17,
-          tableLength: 6,
-          requestParam: 'cat',
-        },
-        {
-          variable: 8,
-          current: 8,
-          index: 5,
-          previous: 7,
-          next: 2,
-          lastAll: 2,
-          sumAllPrevious: 26,
-          sumWhereMatchingOrgUnit: 17,
-          tableLength: 6,
-          requestParam: 'cat',
-        },
-        {
-          variable: 2,
-          current: 2,
-          index: 6,
-          previous: 8,
-          lastAll: 2,
-          sumAllPrevious: 28,
-          sumWhereMatchingOrgUnit: 17,
-          tableLength: 6,
-          requestParam: 'cat',
-        },
-      ]),
+    expect(transform(TransformTable.fromRows(PARSABLE_ANALYTICS))).toStrictEqual(
+      TransformTable.fromRows(
+        [
+          {
+            variable: 4,
+            current: 4,
+            index: 1,
+            next: 2,
+            lastAll: 2,
+            sumAllPrevious: 4,
+            sumWhereMatchingOrgUnit: 11,
+            tableLength: 6,
+            requestParam: 'cat',
+          },
+          {
+            variable: 2,
+            current: 2,
+            index: 2,
+            previous: 4,
+            next: 5,
+            lastAll: 2,
+            sumAllPrevious: 6,
+            sumWhereMatchingOrgUnit: 11,
+            tableLength: 6,
+            requestParam: 'cat',
+          },
+          {
+            variable: 5,
+            current: 5,
+            index: 3,
+            previous: 2,
+            next: 7,
+            lastAll: 2,
+            sumAllPrevious: 11,
+            sumWhereMatchingOrgUnit: 11,
+            tableLength: 6,
+            requestParam: 'cat',
+          },
+          {
+            variable: 7,
+            current: 7,
+            index: 4,
+            previous: 5,
+            next: 8,
+            lastAll: 2,
+            sumAllPrevious: 18,
+            sumWhereMatchingOrgUnit: 17,
+            tableLength: 6,
+            requestParam: 'cat',
+          },
+          {
+            variable: 8,
+            current: 8,
+            index: 5,
+            previous: 7,
+            next: 2,
+            lastAll: 2,
+            sumAllPrevious: 26,
+            sumWhereMatchingOrgUnit: 17,
+            tableLength: 6,
+            requestParam: 'cat',
+          },
+          {
+            variable: 2,
+            current: 2,
+            index: 6,
+            previous: 8,
+            lastAll: 2,
+            sumAllPrevious: 28,
+            sumWhereMatchingOrgUnit: 17,
+            tableLength: 6,
+            requestParam: 'cat',
+          },
+        ],
+        [
+          'variable',
+          'current',
+          'index',
+          'previous',
+          'next',
+          'lastAll',
+          'sumAllPrevious',
+          'sumWhereMatchingOrgUnit',
+          'tableLength',
+          'requestParam',
+        ],
+      ),
     );
   });
 
@@ -120,13 +133,16 @@ describe('parser', () => {
           where: "=eq($organisationUnit, 'TO')",
         },
       ]);
-      expect(transform(TransformTable.fromRows(PARSABLE_ANALYTICS))).toEqual(
-        TransformTable.fromRows([
-          { period: undefined, organisationUnit: undefined, BCD1: 11 },
-          { period: '20200101', organisationUnit: 'PG', BCD1: 7 },
-          { period: '20200102', organisationUnit: 'PG', BCD1: 8 },
-          { period: '20200103', organisationUnit: 'PG', BCD1: 2 },
-        ]),
+      expect(transform(TransformTable.fromRows(PARSABLE_ANALYTICS))).toStrictEqual(
+        TransformTable.fromRows(
+          [
+            { BCD1: 11 },
+            { period: '20200101', organisationUnit: 'PG', BCD1: 7 },
+            { period: '20200102', organisationUnit: 'PG', BCD1: 8 },
+            { period: '20200103', organisationUnit: 'PG', BCD1: 2 },
+          ],
+          ['period', 'organisationUnit', 'BCD1'],
+        ),
       );
     });
 
@@ -138,7 +154,7 @@ describe('parser', () => {
             '=$BCD1 <= mean(where(f(@otherRow) = eq($organisationUnit, @otherRow.organisationUnit)).BCD1)',
         },
       ]);
-      expect(transform(TransformTable.fromRows(PARSABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(PARSABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
           { period: '20200101', organisationUnit: 'TO', BCD1: 4 },
           { period: '20200103', organisationUnit: 'TO', BCD1: 5 },
@@ -158,7 +174,7 @@ describe('parser', () => {
           exclude: ['organisationUnit', 'BCD1'],
         },
       ]);
-      expect(transform(TransformTable.fromRows(PARSABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(PARSABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
           { period: '20200101', TO: 4 },
           { period: '20200102', TO: 2 },
@@ -177,7 +193,7 @@ describe('parser', () => {
           by: '=$BCD1',
         },
       ]);
-      expect(transform(TransformTable.fromRows(PARSABLE_ANALYTICS))).toEqual(
+      expect(transform(TransformTable.fromRows(PARSABLE_ANALYTICS))).toStrictEqual(
         TransformTable.fromRows([
           { period: '20200102', organisationUnit: 'TO', BCD1: 2 },
           { period: '20200103', organisationUnit: 'PG', BCD1: 2 },
diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/sortRows.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/sortRows.test.ts
index d40e5c8269..53e5b7893e 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/sortRows.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/sortRows.test.ts
@@ -25,7 +25,7 @@ describe('sortRows', () => {
         by: 'period',
       },
     ]);
-    expect(transform(TransformTable.fromRows(SORTABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(SORTABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', BCD1: 4 },
         { period: '20200101', organisationUnit: 'TO', BCD1: 11 },
@@ -51,7 +51,7 @@ describe('sortRows', () => {
         direction: 'desc',
       },
     ]);
-    expect(transform(TransformTable.fromRows(SORTABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(SORTABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200103', organisationUnit: 'TO', BCD1: 5 },
         { period: '20200103', organisationUnit: 'TO', BCD1: 0 },
@@ -76,7 +76,7 @@ describe('sortRows', () => {
         by: ['period', 'organisationUnit'],
       },
     ]);
-    expect(transform(TransformTable.fromRows(SORTABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(SORTABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'PG', BCD1: 7 },
         { period: '20200101', organisationUnit: 'PG', BCD1: 13 },
@@ -102,7 +102,7 @@ describe('sortRows', () => {
         direction: ['asc', 'desc'],
       },
     ]);
-    expect(transform(TransformTable.fromRows(SORTABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(SORTABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'PG', BCD1: 13 },
         { period: '20200101', organisationUnit: 'TO', BCD1: 11 },
@@ -127,7 +127,7 @@ describe('sortRows', () => {
         by: '=$BCD1 * $BCD1',
       },
     ]);
-    expect(transform(TransformTable.fromRows(SORTABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(SORTABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200103', organisationUnit: 'TO', BCD1: 0 },
         { period: '20200102', organisationUnit: 'TO', BCD1: 1 },
diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/transform.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/transform.test.ts
index 083be5569e..3f52c3fa09 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/transform.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/transform.test.ts
@@ -42,7 +42,7 @@ describe('transform', () => {
         exclude: '*',
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([{ Total: 11 }]),
     );
   });
@@ -74,7 +74,7 @@ describe('transform', () => {
         exclude: '*',
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([{ Total: 11 }]),
     );
   });
diff --git a/packages/report-server/src/__tests__/reportBuilder/transform/updateColumns.test.ts b/packages/report-server/src/__tests__/reportBuilder/transform/updateColumns.test.ts
index ba2ece8b33..39dbe6cf0e 100644
--- a/packages/report-server/src/__tests__/reportBuilder/transform/updateColumns.test.ts
+++ b/packages/report-server/src/__tests__/reportBuilder/transform/updateColumns.test.ts
@@ -13,7 +13,7 @@ describe('updateColumns', () => {
         transform: 'updateColumns',
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0] }]),
     );
   });
@@ -29,7 +29,7 @@ describe('updateColumns', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0], number: 1, string: 'Hi', boolean: false }]),
     );
   });
@@ -43,7 +43,7 @@ describe('updateColumns', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0], dataElementValue: 4 }]),
     );
   });
@@ -57,7 +57,7 @@ describe('updateColumns', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0], BCD1: 4 }]),
     );
   });
@@ -71,7 +71,7 @@ describe('updateColumns', () => {
         },
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ ...SINGLE_ANALYTIC[0], period: '1st Jan 2020' }]),
     );
   });
@@ -86,7 +86,7 @@ describe('updateColumns', () => {
         include: '*',
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([
         { period: '1st Jan 2020', organisationUnit: 'TO', dataElement: 'BCD1', value: 4 },
       ]),
@@ -103,7 +103,7 @@ describe('updateColumns', () => {
         include: ['organisationUnit', 'value'],
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ organisationUnit: 'TO', value: 4, period: '1st Jan 2020' }]),
     );
   });
@@ -118,7 +118,7 @@ describe('updateColumns', () => {
         exclude: '*',
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ period: '1st Jan 2020' }]),
     );
   });
@@ -133,7 +133,7 @@ describe('updateColumns', () => {
         exclude: ['organisationUnit', 'value'],
       },
     ]);
-    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toEqual(
+    expect(transform(TransformTable.fromRows(SINGLE_ANALYTIC))).toStrictEqual(
       TransformTable.fromRows([{ period: '1st Jan 2020', dataElement: 'BCD1' }]),
     );
   });
@@ -149,7 +149,7 @@ describe('updateColumns', () => {
         include: ['organisationUnit'],
       },
     ]);
-    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MULTIPLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { organisationUnit: 'TO', period: '1st Jan 2020', BCD1: 4 },
         { organisationUnit: 'TO', period: '2nd Jan 2020', BCD1: 2 },
@@ -169,7 +169,7 @@ describe('updateColumns', () => {
         include: ['period', 'organisationUnit'],
       },
     ]);
-    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toEqual(
+    expect(transform(TransformTable.fromRows(MERGEABLE_ANALYTICS))).toStrictEqual(
       TransformTable.fromRows([
         { period: '20200101', organisationUnit: 'TO', newVal: 8 },
         { period: '20200102', organisationUnit: 'TO', newVal: 4 },
diff --git a/packages/report-server/src/reportBuilder/transform/functions/mergeRows/mergeRows.ts b/packages/report-server/src/reportBuilder/transform/functions/mergeRows/mergeRows.ts
index b7f7addb51..1cde67feda 100644
--- a/packages/report-server/src/reportBuilder/transform/functions/mergeRows/mergeRows.ts
+++ b/packages/report-server/src/reportBuilder/transform/functions/mergeRows/mergeRows.ts
@@ -107,7 +107,9 @@ const mergeGroups = (groups: Group[], params: MergeRowsParams) => {
     Object.entries(group).forEach(([columnName, groupValues]) => {
       const mergeStrategy = params.getMergeStrategy(columnName);
       const mergedValue = mergeStrategies[mergeStrategy](groupValues);
-      mergedRow[columnName] = mergedValue;
+      if (mergedValue !== undefined) {
+        mergedRow[columnName] = mergedValue;
+      }
     });
     return mergedRow;
   });
diff --git a/packages/report-server/src/reportBuilder/transform/table/TransformTable.ts b/packages/report-server/src/reportBuilder/transform/table/TransformTable.ts
index 6ce3a93d79..829ef15a52 100644
--- a/packages/report-server/src/reportBuilder/transform/table/TransformTable.ts
+++ b/packages/report-server/src/reportBuilder/transform/table/TransformTable.ts
@@ -147,7 +147,12 @@ export class TransformTable {
     }
 
     values.forEach((value, index) => {
-      this.rows[index][columnName] = value;
+      if (isExistingColumn) {
+        delete this.rows[index][columnName];
+      }
+      if (value !== undefined) {
+        this.rows[index][columnName] = value;
+      }
     });
   }