[IMPALA-6374] test tpcds-q98.test has some incorrect data

• Type: Test
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: Impala 2.9.0
• Fix Version/s: Impala 3.1.0
• Component/s: Infrastructure
• Target Version: Impala 3.2.0
• Epic Color: ghx-label-6
• Assignee: Tim Armstrong
• Reporter: Stephen Carlin
• Created: 07/Jan/18 13:45
• Updated: 30/Oct/18 22:26
• Resolved: 30/Oct/18 22:26

Description

I happened to look through the unit tests and it looks like tpcds-q98.test has some bad data in it, but it is verifying correctly.

One example (among maybe 12 or so) is on line 469:
line 468: 'AAAAAAAAEKGDAAAA','Houses should ','Books','mystery',1.77,3341.80,1.96
line 469: 'AAAAAAAAFFDDAAAA',','Books','mystery',2.79,4237.23,2.49

Note that the 2nd field for line 468 looks normal, but line 469 has just a single quote.

I believe this is happening on all strings that end with a comma for this test. The correct result for this line (I believe) should be (note the comma after Poor):
'AAAAAAAAFFDDAAAA','French, civil hours must report essential values. Reasonable, complete judges vary clearly homes; often pleasant women would watch. Poor,','Books','mystery',2.79,4237.23,2.48

My guess as to why this is happening is some code in test_result_verifier.py, specifically in the part that says:
for col_val in row_string.split(','):

1. This is a bit tricky because we need to handle the case where a comma may be in
2. the middle of a string. We detect this by finding a split that starts with an
3. opening string character but that doesn't end in a string character. It is
4. possible for the first character to be a single-quote, so handle that case
   if (col_val.startswith("'") and not col_val.endswith("'")) or (col_val == "'"):