Github user Ben-Zvi commented on a diff in the pull request:
https://github.com/apache/drill/pull/1057#discussion_r153934729
--- Diff:
exec/java-exec/src/main/java/org/apache/drill/exec/record/VectorContainer.java
---
@@ -353,6 +353,23 @@ public int getRecordCount() {
public boolean hasRecordCount() { return recordCount != -1; }
+ /**
+ * This works with non-hyper {@link VectorContainer}s which have no
selection vectors.
+ * Appends a row taken from a source {@link VectorContainer} to this
{@link VectorContainer}.
+ * @param srcContainer The {@link VectorContainer} to copy a row from.
+ * @param srcIndex The index of the row to copy from the source {@link
VectorContainer}.
+ */
+ public void appendRow(VectorContainer srcContainer, int srcIndex) {
+ for (int vectorIndex = 0; vectorIndex < wrappers.size();
vectorIndex++) {
+ ValueVector destVector = wrappers.get(vectorIndex).getValueVector();
+ ValueVector srcVector =
srcContainer.wrappers.get(vectorIndex).getValueVector();
+
+ destVector.copyEntry(recordCount, srcVector, srcIndex);
+ }
+
+ recordCount++;
--- End diff --
The immediate need for appendRow() is to distribute rows from a single
incoming batch into multiple other batches (for the Hash Join internal
partitioning), based on the hash value of the key columns at each row. This
would not work well with the second suggestion (vectorizing - column 1, column
2, etc.)
---
