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https://issues.apache.org/jira/browse/CASSANDRA-21139?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18073420#comment-18073420
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Rishabh Saraswat commented on CASSANDRA-21139:
----------------------------------------------

Here's a summary of changes
 * Excludes insert statements from check - [Insert's grammar 
|[https://github.com/apache/cassandra/blob/trunk/doc%2Fcql3%2FCQL.textile], 
|https://github.com/apache/cassandra/blob/trunk/doc%2Fcql3%2FCQL.textile],]<insertStatement>
 ::= INSERT INTO <tablename>
                      ( ( <name-list> VALUES <value-list> )
                      | ( JSON <string> (DEFAULT ( NULL | UNSET ))?))
                      ( IF NOT EXISTS )?
                      ( USING <option> ( AND <option> )* )?
no WHERE clause
 * insert statements can't have where blocks, so excluded them as they are an 
instance of ModificationStatement same as update and delete statementa.
 * Warning statements will include keyspace and table name to trace to mis 
prepared query easy.
 * As parameter was renamed, changed the semantics of docs too.

> Guardrail for miss-prepared statements
> --------------------------------------
>
>                 Key: CASSANDRA-21139
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-21139
>             Project: Apache Cassandra
>          Issue Type: Improvement
>          Components: Feature/Guardrails
>            Reporter: Brad Schoening
>            Assignee: Rishabh Saraswat
>            Priority: Normal
>             Fix For: 6.x
>
>         Attachments: Positive Failure.png, Server Side Logging.png, script.txt
>
>          Time Spent: 12h
>  Remaining Estimate: 0h
>
> We have hundreds of application teams and several dozen of them miss-prepare 
> statements by using literals instead of bind markers.  
> I.e., 
> {code:sql}
> // wrong 
> session.prepare("select * from users where ID = 996");
> session.prepare("select * from users where ID = 997");
> session.prepare("select * from users where ID = 998");
> session.prepare("select * from users where ID = 999");
> // correct
> session.prepare("select * from users where ID = ?");
> {code}
> The problem causes the prepared statement cache to constantly overflow, and 
> will print a prepared statements discarded WARN message in the Cassandra log. 
>  At present, we use a wack-a-mole approach to discuss the problem with each 
> development team individually, and hope they fix it and train the entire team 
> on how to prepare statements correctly.
> Also, finding the root cause of the issue today requires having the knowledge 
> and access to look at the system.prepared_statements table.
> Guardrails would seem a good approach here, where the guard could WARN or 
> REJECT when a statement was prepared using a WHERE clause and no bind markers.
> Note, this should not prevent users from creating prepared statements without 
> a WHERE clause or with one or more literal values so long as there was at 
> least one bind marker.  Thus, the following would remain valid:
> {code:sql}
> session.prepare("select * from users");
> session.prepare("select * from users where TYPE=5 and ID = ?");
> {code}



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