[SOLR-12010] Better error handling for Parallel SQL queries

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 8.0
• Component/s: Parallel SQL
• Assignee: Unassigned
• Reporter: Amrit Sarkar
• Created: 21/Feb/18 05:06
• Updated: 08/Jun/19 15:14

Description

While building examples in Parallel SQL queries, we encountered strange error messages which didn't make sense unless you look deeply into the code, in my case, using debugger on source code to understand better.

e.g.

curl --data-urlencode 'stmt=select emp_no_s,emp_no_s from salaries 
    group by emp_no_s
    limit 10' http://localhost:8983/solr/employees/sql?aggregationMode=map_reduce

aggregate-field 'emp_no_s' is asked to group-by twice and hence this is runtime SQL error, while error message received in solr logs:

Caused by: java.sql.SQLException: Error while executing SQL "select emp_no_s,emp_no_s from salaries 
    group by emp_no_s
    limit 10": 1
        at org.apache.calcite.avatica.Helper.createException(Helper.java:56)
        at org.apache.calcite.avatica.Helper.createException(Helper.java:41)
        at org.apache.calcite.avatica.AvaticaStatement.executeInternal(AvaticaStatement.java:156)
        at org.apache.calcite.avatica.AvaticaStatement.executeQuery(AvaticaStatement.java:218)
        at org.apache.solr.client.solrj.io.stream.JDBCStream.open(JDBCStream.java:269)
        ... 41 more
Caused by: java.lang.ArrayIndexOutOfBoundsException: 1
        at org.apache.solr.handler.sql.SolrTable.buildBuckets(SolrTable.java:559)
        at org.apache.solr.handler.sql.SolrTable.handleGroupByMapReduce(SolrTable.java:445)
        at org.apache.solr.handler.sql.SolrTable.query(SolrTable.java:135)
        at org.apache.solr.handler.sql.SolrTable.access$100(SolrTable.java:64)
        at org.apache.solr.handler.sql.SolrTable$SolrQueryable.query(SolrTable.java:859)
        at Baz.bind(Unknown Source)
        at org.apache.calcite.jdbc.CalcitePrepare$CalciteSignature.enumerable(CalcitePrepare.java:335)
        at org.apache.calcite.jdbc.CalciteConnectionImpl.enumerable(CalciteConnectionImpl.java:294)
        at org.apache.calcite.jdbc.CalciteMetaImpl._createIterable(CalciteMetaImpl.java:559)
        at org.apache.calcite.jdbc.CalciteMetaImpl.createIterable(CalciteMetaImpl.java:550)
        at org.apache.calcite.avatica.AvaticaResultSet.execute(AvaticaResultSet.java:204)
        at org.apache.calcite.jdbc.CalciteResultSet.execute(CalciteResultSet.java:67)
        at org.apache.calcite.jdbc.CalciteResultSet.execute(CalciteResultSet.java:44)
        at org.apache.calcite.avatica.AvaticaConnection$1.execute(AvaticaConnection.java:630)
        at org.apache.calcite.jdbc.CalciteMetaImpl.prepareAndExecute(CalciteMetaImpl.java:607)
        at org.apache.calcite.avatica.AvaticaConnection.prepareAndExecuteInternal(AvaticaConnection.java:638)
        at org.apache.calcite.avatica.AvaticaStatement.executeInternal(AvaticaStatement.java:149)
        ... 43 more