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https://issues.apache.org/jira/browse/CASSANDRA-12573?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15501413#comment-15501413
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DOAN DuyHai commented on CASSANDRA-12573:
-----------------------------------------

bq. That's good news. When do you plan to merge it?
See this JIRA:  [CASSANDRA-10765] (second comment)

bq. As a customer I have a slightly different view on this. My expectations are 
based on prior experience and common sense.

 What are you talking about ? Customer of what ? Apache Cassandra is 
open-source.

bq. My current impression is that this feature is half-baked and not well 
tested. But it's just my opinion.

Well that are the risks of open source software, you don't have any strong 
guarantees/SLA or whatsoever. But you can contribute to improve SASI. Any pull 
request is welcomed of course. The community will be more than happy to have 
contributors

bq. After that I run the queries with '%' inside. As you can see multi-patterns 
are handled by AND:

Absolutely not. Your examples just show how the index mode {{CONTAINS}} works. 

First query {{name like '%RevisionDiff%';}} means give me all names containing 
{{RevisionDiff}} substring

2nd query {{name like '%ItemImpl%';}} means give me all names containing 
{{ItemImpl}} substring

3rd query {{name like '%RevisionDiff%ItemImpl%';}} means give me all names 
containing {{RevisionDiff}} substring OR 'ItemImpl' substring

Nowhere I see the *AND* semantic in your example





> SASI index. Incorrect results for '%foo%bar%'-like search pattern. 
> -------------------------------------------------------------------
>
>                 Key: CASSANDRA-12573
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-12573
>             Project: Cassandra
>          Issue Type: Bug
>            Reporter: Mikhail Krupitskiy
>            Priority: Critical
>              Labels: sasi
>
> We use Cassandra 3.7 and have faced a strange behaviour of SELECT requests 
> with "LIKE '%foo%bar%'" constraints on a column with SASI index.
> Below are few experiments that show this behaviour.
> Experiment 1:
> {noformat}
> drop keyspace if exists kmv;
> create keyspace if not exists kmv WITH REPLICATION = { 'class' : 
> 'SimpleStrategy', 'replication_factor':'1'} ;
> use kmv;
> CREATE TABLE if not exists kmv (id int primary key, c1 text, c2 text);
> CREATE CUSTOM INDEX ON kmv.kmv  ( c2 ) USING 
> 'org.apache.cassandra.index.sasi.SASIIndex' WITH OPTIONS = {
>  'mode': 'CONTAINS'
> };
> insert into kmv (id, c1, c2) values (1, 'f21', 'qwe') ;
> insert into kmv (id, c1, c2) values (2, 'f22', 'qweasd') ;
> insert into kmv (id, c1, c2) values (3, 'f23', 'qwea1') ;
> insert into kmv (id, c1, c2) values (4, 'f24', '1qwe') ;
> insert into kmv (id, c1, c2) values (5, 'f25', 'asdqwe') ;
> select c2 from kmv.kmv where c2 like '%w%a%';
> {noformat}
> Expected result: qweasd, qwea1.
> Actual result: no rows.
> Experiment 2 (NOTE: definition of index is changed):
> {noformat}
> drop keyspace if exists kmv;
> create keyspace if not exists kmv WITH REPLICATION = { 'class' : 
> 'SimpleStrategy', 'replication_factor':'1'} ;
> use kmv;
> CREATE TABLE if not exists kmv (id int primary key, c1 text, c2 text);
> CREATE CUSTOM INDEX ON kmv.kmv  ( c2 ) USING 
> 'org.apache.cassandra.index.sasi.SASIIndex' WITH OPTIONS = {
>  'mode': 'CONTAINS',
>  'analyzer_class': 
> 'org.apache.cassandra.index.sasi.analyzer.StandardAnalyzer',
>  'analyzed': 'true'
> };
> insert into kmv (id, c1, c2) values (1, 'f21', 'qwe') ;
> insert into kmv (id, c1, c2) values (2, 'f22', 'qweasd') ;
> insert into kmv (id, c1, c2) values (3, 'f23', 'qwea1') ;
> insert into kmv (id, c1, c2) values (4, 'f24', '1qwe') ;
> insert into kmv (id, c1, c2) values (5, 'f25', 'asdqwe') ;
> select c2 from kmv.kmv where c2 like '%w%a%';
> {noformat}
> Expected result: qweasd, qwea1.
> Actual result: asdqwe, qweasd, qwea1.
> Experiment 3 (NOTE: primary key is compound now and inserted data was 
> changed):
> {noformat}
> drop keyspace if exists kmv;
> create keyspace if not exists kmv WITH REPLICATION = { 'class' : 
> 'SimpleStrategy', 'replication_factor':'1'} ;
> use kmv;
> CREATE TABLE if not exists kmv (id int, c1 text, c2 text, PRIMARY KEY(id, 
> c1));
> CREATE CUSTOM INDEX ON kmv.kmv  ( c2 ) USING 
> 'org.apache.cassandra.index.sasi.SASIIndex' WITH OPTIONS = {
>  'mode': 'CONTAINS',
>  'analyzer_class': 
> 'org.apache.cassandra.index.sasi.analyzer.StandardAnalyzer',
>  'analyzed': 'true'
> };
> insert into kmv (id, c1, c2) values (1, 'f21', 'qwe') ;
> insert into kmv (id, c1, c2) values (1, 'f22', 'qweasd') ;
> insert into kmv (id, c1, c2) values (1, 'f23', 'qwea1') ;
> insert into kmv (id, c1, c2) values (1, 'f24', '1qwe') ;
> insert into kmv (id, c1, c2) values (1, 'f25', 'asdqwe') ;
> select c2 from kmv.kmv where c2 like '%w%a%';
> {noformat}
> Expected result: qweasd, qwea1.
> Actual result: qwe, qweasd, qwea1, 1qwe, asdqwe.
> Experiment 4 (NOTE: search criteria is changed):
> {noformat}
> drop keyspace if exists kmv;
> create keyspace if not exists kmv WITH REPLICATION = { 'class' : 
> 'SimpleStrategy', 'replication_factor':'1'} ;
> use kmv;
> CREATE TABLE if not exists kmv (id int, c1 text, c2 text, PRIMARY KEY(id, 
> c1));
> CREATE CUSTOM INDEX ON kmv.kmv  ( c2 ) USING 
> 'org.apache.cassandra.index.sasi.SASIIndex' WITH OPTIONS = {
>  'mode': 'CONTAINS',
>  'analyzer_class': 
> 'org.apache.cassandra.index.sasi.analyzer.StandardAnalyzer',
>  'analyzed': 'true'
> };
> insert into kmv (id, c1, c2) values (1, 'f21', 'qwe') ;
> insert into kmv (id, c1, c2) values (1, 'f22', 'qweasd') ;
> insert into kmv (id, c1, c2) values (1, 'f23', 'qwea1') ;
> insert into kmv (id, c1, c2) values (1, 'f24', '1qwe') ;
> insert into kmv (id, c1, c2) values (1, 'f25', 'asdqwe') ;
> select c2 from kmv.kmv where c2 like '%w22%a%';
> {noformat}
> Expected result: no rows.
> Actual result: qweasd, qwea1, asdqwe.



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