[postgresql] Fix for #4300 -- ambiguity in from_list #4301
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This was referenced Nov 3, 2024
kaby76
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@kaby76 thanks! |
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This PR fixes a grammar ambiguity introduced with #3008.
Consider input
select x from t c1, t c2;. The substringt c1, t c2can be parsed two ways:from_list=>non_ansi_join=>table_ref ...==>t c1, t c2from_list=>table_ref ...==>t c1, t c2As I point out in the write-up for #4300, from_list is defined with two alts that overlap. The two alts did not fix anything. It simply added to the ambiguity of the grammar and made the parser perform worse.
I discovered this using trparse --ambig.