Re: pgsql: Get rid of backtracking in jsonpath_scan.l

On 3/25/19 8:44 AM, Alexander Korotkov wrote:
> Get rid of backtracking in jsonpath_scan.l
>
> Non-backtracking flex parsers work faster than backtracking ones.  So, this
> commit gets rid of backtracking in jsonpath_scan.l.  That required explicit
> handling of some cases as well as manual backtracking for some cases.  More
> regression tests for numerics are added.



jacana appears to be having trouble with this:


2019-03-26 00:49:02.208 EDT [5c99ae9e.20cc:6] LOG:  server process (PID 8368) was terminated by exception 0xC0000028
2019-03-26 00:49:02.208 EDT [5c99ae9e.20cc:7] DETAIL:  Failed process was running: select '$ ? (@ like_regex "pattern"
flag"a")'::jsonpath;
 
2019-03-26 00:49:02.208 EDT [5c99ae9e.20cc:8] HINT:  See C include file "ntstatus.h" for a description of the
hexadecimalvalue.
 
2019-03-26 00:49:02.208 EDT [5c99ae9e.20cc:9] LOG:  terminating any other active server processes

cheers

andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
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