diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/first/DoubleFirstAggregator.java b/processing/src/main/java/org/apache/druid/query/aggregation/first/DoubleFirstAggregator.java
index f713a15de190..cf121f72fc98 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/first/DoubleFirstAggregator.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/first/DoubleFirstAggregator.java
@@ -34,7 +34,7 @@ public DoubleFirstAggregator(BaseLongColumnValueSelector timeSelector, ColumnVal
   }
 
   @Override
-  void setFirstValue(ColumnValueSelector valueSelector)
+  void setFirstValue()
   {
     firstValue = valueSelector.getDouble();
   }
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/first/DoubleFirstAggregatorFactory.java b/processing/src/main/java/org/apache/druid/query/aggregation/first/DoubleFirstAggregatorFactory.java
index dc042aa2ab93..be3bce7ae02e 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/first/DoubleFirstAggregatorFactory.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/first/DoubleFirstAggregatorFactory.java
@@ -238,7 +238,6 @@ public byte[] getCacheKey()
   @Override
   public ColumnType getIntermediateType()
   {
-    // if we don't pretend to be a primitive, group by v1 gets sad and doesn't work because no complex type serde
     return TYPE;
   }
 
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/first/FloatFirstAggregator.java b/processing/src/main/java/org/apache/druid/query/aggregation/first/FloatFirstAggregator.java
index d02bfdb922cd..987937c2ba87 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/first/FloatFirstAggregator.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/first/FloatFirstAggregator.java
@@ -38,7 +38,7 @@ public FloatFirstAggregator(
   }
 
   @Override
-  void setFirstValue(ColumnValueSelector valueSelector)
+  void setFirstValue()
   {
     firstValue = valueSelector.getFloat();
   }
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/first/FloatFirstAggregatorFactory.java b/processing/src/main/java/org/apache/druid/query/aggregation/first/FloatFirstAggregatorFactory.java
index 7884ea4a9280..0336aaaa294d 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/first/FloatFirstAggregatorFactory.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/first/FloatFirstAggregatorFactory.java
@@ -235,7 +235,6 @@ public byte[] getCacheKey()
   @Override
   public ColumnType getIntermediateType()
   {
-    // if we don't pretend to be a primitive, group by v1 gets sad and doesn't work because no complex type serde
     return TYPE;
   }
 
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/first/LongFirstAggregator.java b/processing/src/main/java/org/apache/druid/query/aggregation/first/LongFirstAggregator.java
index af070dbb5e8c..d229819382e9 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/first/LongFirstAggregator.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/first/LongFirstAggregator.java
@@ -34,7 +34,7 @@ public LongFirstAggregator(BaseLongColumnValueSelector timeSelector, ColumnValue
   }
 
   @Override
-  void setFirstValue(ColumnValueSelector valueSelector)
+  void setFirstValue()
   {
     firstValue = valueSelector.getLong();
   }
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/first/LongFirstAggregatorFactory.java b/processing/src/main/java/org/apache/druid/query/aggregation/first/LongFirstAggregatorFactory.java
index 3ecaabf15971..27cad349ead4 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/first/LongFirstAggregatorFactory.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/first/LongFirstAggregatorFactory.java
@@ -234,7 +234,6 @@ public byte[] getCacheKey()
   @Override
   public ColumnType getIntermediateType()
   {
-    // if we don't pretend to be a primitive, group by v1 gets sad and doesn't work because no complex type serde
     return TYPE;
   }
 
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/first/NumericFirstAggregator.java b/processing/src/main/java/org/apache/druid/query/aggregation/first/NumericFirstAggregator.java
index b7f88f963fed..b3092377b578 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/first/NumericFirstAggregator.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/first/NumericFirstAggregator.java
@@ -52,7 +52,7 @@ public NumericFirstAggregator(BaseLongColumnValueSelector timeSelector, ColumnVa
   /**
    * Store the current primitive typed 'first' value
    */
-  abstract void setFirstValue(ColumnValueSelector valueSelector);
+  abstract void setFirstValue();
 
   /**
    * Store a non-null first value
@@ -71,7 +71,7 @@ public void aggregate()
       if (object instanceof SerializablePair) {
         SerializablePair<Long, Number> inPair = (SerializablePair<Long, Number>) object;
 
-        if (inPair != null && inPair.lhs < firstTime) {
+        if (inPair.lhs < firstTime) {
           firstTime = inPair.lhs;
           if (inPair.rhs == null) {
             rhsNull = true;
@@ -88,7 +88,7 @@ public void aggregate()
     if (time < firstTime) {
       firstTime = time;
       if (useDefault || !valueSelector.isNull()) {
-        setFirstValue(valueSelector);
+        setFirstValue();
         rhsNull = false;
       } else {
         setFirstValue(0);
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/first/NumericFirstBufferAggregator.java b/processing/src/main/java/org/apache/druid/query/aggregation/first/NumericFirstBufferAggregator.java
index c9911399ed11..4531ee71bcd6 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/first/NumericFirstBufferAggregator.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/first/NumericFirstBufferAggregator.java
@@ -106,7 +106,7 @@ public void aggregate(ByteBuffer buf, int position)
       final Object object = valueSelector.getObject();
       if (object instanceof SerializablePair) {
         final SerializablePair<Long, Number> inPair = (SerializablePair<Long, Number>) object;
-        if (inPair != null && inPair.lhs < firstTime) {
+        if (inPair.lhs < firstTime) {
           if (inPair.rhs == null) {
             updateTimeWithNull(buf, position, inPair.lhs);
           } else {
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/last/DoubleLastAggregator.java b/processing/src/main/java/org/apache/druid/query/aggregation/last/DoubleLastAggregator.java
index e5eca666986d..009e9c82333f 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/last/DoubleLastAggregator.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/last/DoubleLastAggregator.java
@@ -34,7 +34,7 @@ public DoubleLastAggregator(BaseLongColumnValueSelector timeSelector, ColumnValu
   }
 
   @Override
-  void setLastValue(ColumnValueSelector valueSelector)
+  void setLastValue()
   {
     lastValue = valueSelector.getDouble();
   }
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/last/DoubleLastAggregatorFactory.java b/processing/src/main/java/org/apache/druid/query/aggregation/last/DoubleLastAggregatorFactory.java
index de6e707310f7..55da0be236a3 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/last/DoubleLastAggregatorFactory.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/last/DoubleLastAggregatorFactory.java
@@ -265,7 +265,6 @@ public byte[] getCacheKey()
   @Override
   public ColumnType getIntermediateType()
   {
-    // if we don't pretend to be a primitive, group by v1 gets sad and doesn't work because no complex type serde
     return TYPE;
   }
 
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/last/FloatLastAggregator.java b/processing/src/main/java/org/apache/druid/query/aggregation/last/FloatLastAggregator.java
index c55fbb997baa..63147a92db77 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/last/FloatLastAggregator.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/last/FloatLastAggregator.java
@@ -34,7 +34,7 @@ public FloatLastAggregator(BaseLongColumnValueSelector timeSelector, ColumnValue
   }
 
   @Override
-  void setLastValue(ColumnValueSelector valueSelector)
+  void setLastValue()
   {
     lastValue = valueSelector.getFloat();
   }
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/last/FloatLastAggregatorFactory.java b/processing/src/main/java/org/apache/druid/query/aggregation/last/FloatLastAggregatorFactory.java
index a42491013dbb..a97eb5f61fd3 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/last/FloatLastAggregatorFactory.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/last/FloatLastAggregatorFactory.java
@@ -264,7 +264,6 @@ public byte[] getCacheKey()
   @Override
   public ColumnType getIntermediateType()
   {
-    // if we don't pretend to be a primitive, group by v1 gets sad and doesn't work because no complex type serde
     return TYPE;
   }
 
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/last/LongLastAggregator.java b/processing/src/main/java/org/apache/druid/query/aggregation/last/LongLastAggregator.java
index b07c3784aaeb..f5f5791da960 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/last/LongLastAggregator.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/last/LongLastAggregator.java
@@ -34,7 +34,7 @@ public LongLastAggregator(BaseLongColumnValueSelector timeSelector, ColumnValueS
   }
 
   @Override
-  void setLastValue(ColumnValueSelector valueSelector)
+  void setLastValue()
   {
     lastValue = valueSelector.getLong();
   }
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/last/LongLastAggregatorFactory.java b/processing/src/main/java/org/apache/druid/query/aggregation/last/LongLastAggregatorFactory.java
index 51063bdb5d94..bb407400106c 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/last/LongLastAggregatorFactory.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/last/LongLastAggregatorFactory.java
@@ -262,7 +262,6 @@ public byte[] getCacheKey()
   @Override
   public ColumnType getIntermediateType()
   {
-    // if we don't pretend to be a primitive, group by v1 gets sad and doesn't work because no complex type serde
     return TYPE;
   }
 
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/last/NumericLastAggregator.java b/processing/src/main/java/org/apache/druid/query/aggregation/last/NumericLastAggregator.java
index 8d36d534a872..36032e71ecef 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/last/NumericLastAggregator.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/last/NumericLastAggregator.java
@@ -54,7 +54,7 @@ public NumericLastAggregator(BaseLongColumnValueSelector timeSelector, ColumnVal
   /**
    * Store the current primitive typed 'last' value
    */
-  abstract void setLastValue(ColumnValueSelector valueSelector);
+  abstract void setLastValue();
 
   abstract void setLastValue(Number lastValue);
 
@@ -70,7 +70,7 @@ public void aggregate()
       if (object instanceof SerializablePair) {
         final SerializablePair<Long, Number> inPair = (SerializablePair<Long, Number>) object;
 
-        if (inPair != null && inPair.lhs >= lastTime) {
+        if (inPair.lhs >= lastTime) {
           lastTime = inPair.lhs;
 
           if (inPair.rhs == null) {
@@ -88,7 +88,7 @@ public void aggregate()
     if (time >= lastTime) {
       lastTime = time;
       if (useDefault || !valueSelector.isNull()) {
-        setLastValue(valueSelector);
+        setLastValue();
         rhsNull = false;
       } else {
         setLastValue(0);
diff --git a/processing/src/main/java/org/apache/druid/query/aggregation/last/NumericLastBufferAggregator.java b/processing/src/main/java/org/apache/druid/query/aggregation/last/NumericLastBufferAggregator.java
index e6f4e6a893b4..9de6f9968878 100644
--- a/processing/src/main/java/org/apache/druid/query/aggregation/last/NumericLastBufferAggregator.java
+++ b/processing/src/main/java/org/apache/druid/query/aggregation/last/NumericLastBufferAggregator.java
@@ -110,7 +110,7 @@ public void aggregate(ByteBuffer buf, int position)
       if (object instanceof SerializablePair) {
         final SerializablePair<Long, Number> inPair = (SerializablePair<Long, Number>) object;
 
-        if (inPair != null && inPair.lhs >= lastTime) {
+        if (inPair.lhs >= lastTime) {
           if (inPair.rhs == null) {
             updateTimeWithNull(buf, position, inPair.lhs);
           } else {