[
https://issues.apache.org/jira/browse/PHOENIX-6141?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17736579#comment-17736579
]
ASF GitHub Bot commented on PHOENIX-6141:
-----------------------------------------
tkhurana commented on code in PR #1575:
URL: https://github.com/apache/phoenix/pull/1575#discussion_r1240113225
##########
phoenix-core/src/main/java/org/apache/phoenix/query/ConnectionQueryServicesImpl.java:
##########
@@ -2203,6 +2196,89 @@ public MetaDataResponse call(MetaDataService instance)
throws IOException {
return rpcCallback.get();
}
});
+
+ //For view creation, if SYSCAT rpc succeeds, mark child_link rows as
VERIFIED
+ if (!childLinkMutations.isEmpty()) {
+ try {
+ if (result.getMutationCode() == MutationCode.TABLE_NOT_FOUND) {
+ sendChildLinkMutations(childLinkMutations, true, false,
physicalTableNameBytes, schemaBytes);
+ } else {
+ sendChildLinkMutations(childLinkMutations, true, true,
physicalTableNameBytes, schemaBytes);
+ }
+ }
+ catch (SQLException e) {
+ //unverified rows will be repaired during read
+ LOGGER.debug("Exception in phase-3 of view creation: " +
e.getMessage());
+ addChildLinkScanTask();
+ }
+ }
+ return result;
+ }
+
+ /*
+ Helper method to send mutations to SYSTEM.CHILD_LINK using its endpoint
coprocessor
+ */
+ public void sendChildLinkMutations(List<Mutation> mutations, boolean
isVerified, boolean isDelete,
+ byte[] physicalTableNameBytes, byte[]
schemaBytes)
+ throws SQLException {
+
+ // get empty column information
+ PTable childLinkLogicalTable = getTable(null,
PhoenixDatabaseMetaData.SYSTEM_CHILD_LINK_NAME, HConstants.LATEST_TIMESTAMP);
+ byte[] emptyCF =
SchemaUtil.getEmptyColumnFamily(childLinkLogicalTable);
+ byte[] emptyCQ =
EncodedColumnsUtil.getEmptyKeyValueInfo(childLinkLogicalTable).getFirst();
+
+ // add empty column value to mutations or create delete mutations for
phase-3
+ List<Mutation> childLinkMutations = new ArrayList<>();
+ for (Mutation m : mutations) {
+ if (isDelete) {
+ Delete delete = new Delete(m.getRow());
+ childLinkMutations.add(delete);
+ }
+ else {
+ Put put = isVerified ? new Put(m.getRow()) : (Put)m;
+ byte[] emptyColumnValue = isVerified ? VERIFIED_BYTES :
UNVERIFIED_BYTES;
+ put.addColumn(emptyCF, emptyCQ, IndexUtil.getMaxTimestamp(m),
emptyColumnValue);
Review Comment:
But you are setting the timestamp from the existing cells in the mutation
`IndexUtil.getMaxTimestamp(m)`. I am surprised you are getting a higher
timestamp.
> Ensure consistency between SYSTEM.CATALOG and SYSTEM.CHILD_LINK
> ---------------------------------------------------------------
>
> Key: PHOENIX-6141
> URL: https://issues.apache.org/jira/browse/PHOENIX-6141
> Project: Phoenix
> Issue Type: Improvement
> Affects Versions: 5.0.0, 4.15.0
> Reporter: Chinmay Kulkarni
> Assignee: Palash Chauhan
> Priority: Blocker
> Fix For: 5.2.0, 5.1.4
>
>
> Before 4.15, "CREATE/DROP VIEW" was an atomic operation since we were issuing
> batch mutations on just the 1 SYSTEM.CATALOG region. In 4.15 we introduced
> SYSTEM.CHILD_LINK to store the parent->child links and so a CREATE VIEW is no
> longer atomic since it consists of 2 separate RPCs (1 to SYSTEM.CHILD_LINK
> to add the linking row and another to SYSTEM.CATALOG to write metadata for
> the new view).
> If the second RPC i.e. the RPC to write metadata to SYSTEM.CATALOG fails
> after the 1st RPC has already gone through, there will be an inconsistency
> between both metadata tables. We will see orphan parent->child linking rows
> in SYSTEM.CHILD_LINK in this case. This can cause the following issues:
> # ALTER TABLE calls on the base table will fail
> # DROP TABLE without CASCADE will fail
> # The upgrade path has calls like UpgradeUtil.upgradeTable() which will fail
> # Any metadata consistency checks can be thrown off
> # Unnecessary extra storage of orphan links
> The first 3 issues happen because we wrongly deduce that a base table has
> child views due to the orphan linking rows.
> This Jira aims at trying to come up with a way to make mutations among
> SYSTEM.CATALOG and SYSTEM.CHILD_LINK an atomic transaction. We can use a
> 2-phase commit approach like in global indexing or also potentially explore
> using a transaction manager.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
