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https://issues.apache.org/jira/browse/SPARK-21287?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16072388#comment-16072388
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Sean Owen commented on SPARK-21287:
-----------------------------------
Yeah, I'm familiar with this special value.
Is it not equivalent to setting fetch size to 1? or 0? I don't think so, but I
don't recall why. Would it work in your situation and therefore be the right
way to do this for, likely, most callers?
I can see an argument for removing this assertion, but, the JDBC API says that
negative values aren't allowed. This is really nonstandard MySQL behavior, and
it'd be good to find a better way to recommend to users.
> Cannot use Int.MIN_VALUE as Spark SQL fetchsize
> -----------------------------------------------
>
> Key: SPARK-21287
> URL: https://issues.apache.org/jira/browse/SPARK-21287
> Project: Spark
> Issue Type: Bug
> Components: SQL
> Affects Versions: 2.1.1
> Reporter: Maciej Bryński
>
> MySQL JDBC driver gives possibility to not store ResultSet in memory.
> We can do this by setting fetchSize to Int.MIN_VALUE.
> Unfortunately this configuration isn't correct in Spark.
> {code}
> java.lang.IllegalArgumentException: requirement failed: Invalid value
> `-2147483648` for parameter `fetchsize`. The minimum value is 0. When the
> value is 0, the JDBC driver ignores the value and does the estimates.
> at scala.Predef$.require(Predef.scala:224)
> at
> org.apache.spark.sql.execution.datasources.jdbc.JDBCOptions.<init>(JDBCOptions.scala:105)
> at
> org.apache.spark.sql.execution.datasources.jdbc.JDBCOptions.<init>(JDBCOptions.scala:34)
> at
> org.apache.spark.sql.execution.datasources.jdbc.JdbcRelationProvider.createRelation(JdbcRelationProvider.scala:32)
> at
> org.apache.spark.sql.execution.datasources.DataSource.resolveRelation(DataSource.scala:330)
> at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:152)
> at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:125)
> at org.apache.spark.sql.DataFrameReader.jdbc(DataFrameReader.scala:166)
> at org.apache.spark.sql.DataFrameReader.jdbc(DataFrameReader.scala:206)
> at sun.reflect.GeneratedMethodAccessor46.invoke(Unknown Source)
> at
> sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> at java.lang.reflect.Method.invoke(Method.java:498)
> at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
> at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
> at py4j.Gateway.invoke(Gateway.java:280)
> at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
> at py4j.commands.CallCommand.execute(CallCommand.java:79)
> at py4j.GatewayConnection.run(GatewayConnection.java:214)
> at java.lang.Thread.run(Thread.java:748)
> {code}
> https://dev.mysql.com/doc/connector-j/5.1/en/connector-j-reference-implementation-notes.html
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