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https://issues.apache.org/jira/browse/PHOENIX-7032?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17772652#comment-17772652
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ASF GitHub Bot commented on PHOENIX-7032:
-----------------------------------------
tkhurana commented on code in PR #1701:
URL: https://github.com/apache/phoenix/pull/1701#discussion_r1349145357
##########
phoenix-core/src/main/java/org/apache/phoenix/hbase/index/IndexRegionObserver.java:
##########
@@ -917,7 +954,8 @@ private void prepareIndexMutations(BatchMutateContext
context, List<IndexMaintai
for (Pair<IndexMaintainer, HTableInterfaceReference> pair :
indexTables) {
IndexMaintainer indexMaintainer = pair.getFirst();
HTableInterfaceReference hTableInterfaceReference =
pair.getSecond();
- if (nextDataRowState != null) {
+ if (nextDataRowState != null &&
Review Comment:
I think we are not handling the case here when there is an existing row in
the index but after an update the new row doesn't satisfy the index where
condition so it needs to be deleted from the index table.
> Partial Global Secondary Indexes
> --------------------------------
>
> Key: PHOENIX-7032
> URL: https://issues.apache.org/jira/browse/PHOENIX-7032
> Project: Phoenix
> Issue Type: New Feature
> Reporter: Kadir Ozdemir
> Assignee: Kadir Ozdemir
> Priority: Major
>
> The secondary indexes supported in Phoenix have been full indexes such that
> for every data table row there is an index row. Generating an index row for
> every data table row is not always required. For example, some use cases do
> not require index rows for the data table rows in which indexed column values
> are null. Such indexes are called sparse indexes. Partial indexes generalize
> the concept of sparse indexing and allow users to specify the subset of the
> data table rows for which index rows will be maintained. This subset is
> specified using a WHERE clause added to the CREATE INDEX DDL statement.
> Partial secondary indexes were first proposed by Michael Stonebraker
> [here|https://dsf.berkeley.edu/papers/ERL-M89-17.pdf]. Since then several SQL
> databases (e.g.,
> [Postgres|https://www.postgresql.org/docs/current/indexes-partial.html] and
> [SQLite|https://www.sqlite.org/partialindex.html]) and NoSQL databases
> (e.g., [MongoDB|https://www.mongodb.com/docs/manual/core/index-partial/])
> have supported some form of partial indexes. It is challenging to allow
> arbitrary WHERE clauses in DDL statements. For example, Postgres does not
> allow subqueries in these where clauses and SQLite supports much more
> restrictive where clauses.
> Supporting arbitrary where clauses creates challenges for query optimizers in
> deciding the usability of a partial index for a given query. If the set of
> data table rows that satisfy the query is a subset of the data table rows
> that the partial index points back, then the query can use the index. Thus,
> the query optimizer has to decide if the WHERE clause of the query implies
> the WHERE clause of the index.
> Michael Stonebraker [here|https://dsf.berkeley.edu/papers/ERL-M89-17.pdf]
> suggests that an index WHERE clause is a conjunct of simple terms, i.e:
> i-clause-1 and i-clause-2 and ... and i-clause-m where each clause is of the
> form <column> <operator> <constant>. Hence, the qualification can be
> evaluated for each tuple in the indicated relation without consulting
> additional tuples.
> Phoenix partial indexes will initially support a more general set of index
> WHERE clauses that can be evaluated on a single row with the following
> exceptions
> * Subqueries are not allowed.
> * Like expressions are allowed with very limited support such that an index
> WHERE clause with like expressions can imply/contain a query if the query has
> the same like expressions that the index WHERE clause has.
> * Comparison between columns are allowed without supporting transitivity,
> for example, a > b and b > c does not imply a > c.
> Partial indexes will be supported initially for global secondary indexes,
> i.e., covered global indexes and uncovered global indexes. The local
> secondary indexes will be supported in future.
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