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https://issues.apache.org/jira/browse/CASSANDRA-17623?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17539505#comment-17539505
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Doug Rohrer commented on CASSANDRA-17623:
-----------------------------------------

I was the primary author - Yifan figured out that it affected more than just 
the CQLSSTableWriter path and added the test - Francisco and Yifan both paired 
with me for a few hours working on making sure the fix was right, improving 
things like making all of the Map code require a SortedMap implementation vs. 
just fixing the one line that fixed the bug, etc.

So yeah, I think so, but not sure how we'd normally credit that work?

> Frozen maps may be serialized unsorted, causing inability to query later
> ------------------------------------------------------------------------
>
>                 Key: CASSANDRA-17623
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-17623
>             Project: Cassandra
>          Issue Type: Bug
>          Components: CQL/Semantics
>            Reporter: Doug Rohrer
>            Assignee: Doug Rohrer
>            Priority: Normal
>             Fix For: 4.0.x, 4.1-beta, 4.x
>
>          Time Spent: 2h 40m
>  Remaining Estimate: 0h
>
> CASSANDRA-7859 introduced the ability to use frozen collections as parts of 
> primary keys. This +requires+ all frozen maps to be persisted with their 
> entries sorted by the map keys. If the map is +not+ sorted correctly, it 
> becomes impossible to project all of the map values out of the map using the 
> map projection/selection syntax. For example, the select below would fail if 
> the map was not sorted correctly and the higher-valued key was persisted 
> first:
> {code:sql}
> CREATE TABLE test.test (k text, c frozen<map<text, text>>, PRIMARY KEY (k, 
> c));
> INSERT INTO test.test (k, c) VALUES ('key', {'z':'second_value', 
> 'a':'first_value'});
> SELECT k, c['a'] from test.test where k='key' -- c['a'] would return NULL here
> {code}
> Additionally, if you attempted to select just that row by using the complete 
> map value in a WHERE clause, which is also supported, it would return no rows 
> unless the map provided by the query processor just happened to be sorted the 
> same way as the persisted value.
> However, there is a bug in Maps.java where we don't actually use a SortedMap 
> in {{Maps.Value#fromSerialized}}, which manifests if a client sends an 
> unsorted map as a bound parameter to a query on insert or select. In either 
> case, the map may not be sorted correctly, leading to either invalid data 
> being persisted to disk (in the INSERT case) or the query not being able to 
> be executed/returning 0 rows even though a row _should_ exist (SELECT).
> This bug affects any usage of parameterized queries (tested with the DataStax 
> driver, and was originally discovered when using the CQLSSTableWriter code to 
> write data locally).



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