postgres

Commit Graph

Author	SHA1	Message	Date
Tom Lane	e56cad84d5	Fix some minor spec-compliance issues in jsonpath lexer. Although the SQL/JSON tech report makes reference to ECMAScript which allows both single- and double-quoted strings, all the rest of the report speaks only of double-quoted string literals in jsonpaths. That's more compatible with JSON itself; moreover single-quoted strings are hard to use inside a jsonpath that is itself a single-quoted SQL literal. So guess that the intent is to allow only double-quoted literals, and remove lexer support for single-quoted literals. It'll be less painful to add this again later if we're wrong, than to remove a shipped feature. Also, adjust the lexer so that unrecognized backslash sequences are treated as just meaning the escaped character, not as errors. This change has much better support in the standards, as JSON, JavaScript and ECMAScript all make it plain that that's what's supposed to happen. Back-patch to v12. Discussion: https://postgr.es/m/CAPpHfdvDci4iqNF9fhRkTqhe-5_8HmzeLt56drH%2B_Rv2rNRqfg@mail.gmail.com	6 years ago
Alexander Korotkov	1d88a75c42	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. Discussion: https://mail.google.com/mail/u/0?ik=a20b091faa&view=om&permmsgid=msg-f%3A1628425344167939063 Author: John Naylor, Nikita Gluknov, Alexander Korotkov	7 years ago

Author

SHA1

Message

Date

Tom Lane

e56cad84d5

Fix some minor spec-compliance issues in jsonpath lexer.

Although the SQL/JSON tech report makes reference to ECMAScript which
allows both single- and double-quoted strings, all the rest of the
report speaks only of double-quoted string literals in jsonpaths.
That's more compatible with JSON itself; moreover single-quoted strings
are hard to use inside a jsonpath that is itself a single-quoted SQL
literal.  So guess that the intent is to allow only double-quoted
literals, and remove lexer support for single-quoted literals.
It'll be less painful to add this again later if we're wrong, than to
remove a shipped feature.

Also, adjust the lexer so that unrecognized backslash sequences are
treated as just meaning the escaped character, not as errors.  This
change has much better support in the standards, as JSON, JavaScript
and ECMAScript all make it plain that that's what's supposed to
happen.

Back-patch to v12.

Discussion: https://postgr.es/m/CAPpHfdvDci4iqNF9fhRkTqhe-5_8HmzeLt56drH%2B_Rv2rNRqfg@mail.gmail.com

6 years ago

Alexander Korotkov

1d88a75c42

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.

Discussion: https://mail.google.com/mail/u/0?ik=a20b091faa&view=om&permmsgid=msg-f%3A1628425344167939063
Author: John Naylor, Nikita Gluknov, Alexander Korotkov

7 years ago

2 Commits (fe30e7ebfa3846416f1adeb7cf611006513a4ee0)