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Anton Gozhiy commented on DRILL-6962: ------------------------------------- Tested with Drill version 1.16.0-SNAPSHOT (commit 304293a46e66ba27b6b38bbc2fef63743f78d598) Cases verified: - Existing columns with null data - Non-existing columns - Substrings, CTE - Nested coalesce functions (an issue was reported: DRILL-7041) > Function coalesce returns an Error when none of the columns in coalesce exist > in a parquet file > ----------------------------------------------------------------------------------------------- > > Key: DRILL-6962 > URL: https://issues.apache.org/jira/browse/DRILL-6962 > Project: Apache Drill > Issue Type: Improvement > Affects Versions: 1.13.0 > Reporter: Bohdan Kazydub > Assignee: Bohdan Kazydub > Priority: Major > Labels: ready-to-commit > Fix For: 1.16.0 > > > As Drill is schema-free, COALESCE function is expected to return a result and > not error out even if none of the columns being referred to exists in files > being queried. > Here is an example for 2 columns, `unk_col` and `unk_col2`, which do not > exist in the parquet files > {code:java} > select coalesce(unk_col, unk_col2) from dfs.`/tmp/parquetfiles`; > java.lang.IndexOutOfBoundsException: index (0) must be less than size (0) > at > org.apache.drill.shaded.guava.com.google.common.base.Preconditions.checkElementIndex(Preconditions.java:1196) > Fragment 1:0 > [Error Id: 7b9193fb-289b-4fbf-a52a-2b93b01f0cd0 on dkvm2c:31010] > (state=,code=0) > {code} -- This message was sent by Atlassian JIRA (v7.6.3#76005)