[ 
https://issues.apache.org/jira/browse/SPARK-8628?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14601012#comment-14601012
 ] 

Santiago M. Mola commented on SPARK-8628:
-----------------------------------------

Here is an example of failure with Spark 1.4.0:

{code}
[1.152] failure: ``union'' expected but identifier OR found

SELECT CASE a+1 WHEN b THEN 111 WHEN c THEN 222 WHEN d THEN 333 WHEN e THEN 444 
ELSE 555 END, a-b, a FROM t1 WHERE e+d BETWEEN a+b-10 AND c+130 OR a>b OR d>e
                                                                                
                                                                       ^
java.lang.RuntimeException: [1.152] failure: ``union'' expected but identifier 
OR found

SELECT CASE a+1 WHEN b THEN 111 WHEN c THEN 222 WHEN d THEN 333 WHEN e THEN 444 
ELSE 555 END, a-b, a FROM t1 WHERE e+d BETWEEN a+b-10 AND c+130 OR a>b OR d>e
                                                                                
                                                                       ^
        at scala.sys.package$.error(package.scala:27)
{code}

> Race condition in AbstractSparkSQLParser.parse
> ----------------------------------------------
>
>                 Key: SPARK-8628
>                 URL: https://issues.apache.org/jira/browse/SPARK-8628
>             Project: Spark
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 1.3.0, 1.3.1, 1.4.0
>            Reporter: Santiago M. Mola
>            Priority: Critical
>              Labels: regression
>
> SPARK-5009 introduced the following code:
> def parse(input: String): LogicalPlan = {
>     // Initialize the Keywords.
>     lexical.initialize(reservedWords)
>     phrase(start)(new lexical.Scanner(input)) match {
>       case Success(plan, _) => plan
>       case failureOrError => sys.error(failureOrError.toString)
>     }
>   }
> The corresponding initialize method in SqlLexical is not thread-safe:
>   /* This is a work around to support the lazy setting */
>   def initialize(keywords: Seq[String]): Unit = {
>     reserved.clear()
>     reserved ++= keywords
>   }
> I'm hitting this when parsing multiple SQL queries concurrently. When one 
> query parsing starts, it empties the reserved keyword list, then a 
> race-condition occurs and other queries fail to parse because they recognize 
> keywords as identifiers.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org

Reply via email to