If you want to contribute to the project open a JIRA/PR: https://cwiki.apache.org/confluence/display/SPARK/Contributing+to+Spark
On Sat, Dec 12, 2015 at 3:13 AM, [email protected] < [email protected]> wrote: > Hi All, > > > https://github.com/apache/spark/blob/branch-1.5/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/JdbcUtils.scala#L48 > > In Present spark version in line 48 there is a bug, to check whether table > exists in a database using limit doesnt work for all databases sql server > for example. > > best way to check whehter table exists in any database is to use, select * > from table where 1=2; or select 1 from table where 1=2; this supports all > the databases. > > In spark 1.6 can this change be implemented, this lets > write.mode("append") > bug to go away. > > > > def tableExists(conn: Connection, table: String): Boolean = { > > // Somewhat hacky, but there isn't a good way to identify whether a > table exists for all > // SQL database systems, considering "table" could also include the > database name. > Try(conn.prepareStatement(s"SELECT 1 FROM $table LIMIT > 1").executeQuery().next()).isSuccess > } > > Solution:- > def tableExists(conn: Connection, table: String): Boolean = { > > // Somewhat hacky, but there isn't a good way to identify whether a > table exists for all > // SQL database systems, considering "table" could also include the > database name. > Try(conn.prepareStatement(s"SELECT 1 FROM $table where > 1=2").executeQuery().next()).isSuccess > } > > > > Thanks > > > > -- > View this message in context: > http://apache-spark-user-list.1001560.n3.nabble.com/spark-data-frame-write-mode-append-bug-tp25650p25693.html > Sent from the Apache Spark User List mailing list archive at Nabble.com. > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > >
