Add comment

Author: carlosdelest

x-pack/plugin/esql/compute/src/main/java/org/elasticsearch/compute/data/BlockUtils.java

@@ -213,6 +213,7 @@ public static void appendValue(Block.Builder builder, Object val, ElementType ty
             case LONG -> ((LongBlock.Builder) builder).appendLong((Long) val);
             case INT -> ((IntBlock.Builder) builder).appendInt((Integer) val);
             case BYTES_REF -> ((BytesRefBlock.Builder) builder).appendBytesRef(toBytesRef(val));
+            // Dense_vector blocks may be created from double values when retrieved from literals
             case FLOAT -> ((FloatBlock.Builder) builder).appendFloat(((Number) val).floatValue());
             case DOUBLE -> ((DoubleBlock.Builder) builder).appendDouble((Double) val);
             case BOOLEAN -> ((BooleanBlock.Builder) builder).appendBoolean((Boolean) val);