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2146f13408
Since most of the system thinks AND and OR are N-argument expressions anyway, let's have the grammar generate a representation of that form when dealing with input like "x AND y AND z AND ...", rather than generating a deeply-nested binary tree that just has to be flattened later by the planner. This avoids stack overflow in parse analysis when dealing with queries having more than a few thousand such clauses; and in any case it removes some rather unsightly inconsistencies, since some parts of parse analysis were generating N-argument ANDs/ORs already. It's still possible to get a stack overflow with weirdly parenthesized input, such as "x AND (y AND (z AND ( ... )))", but such cases are not mainstream usage. The maximum depth of parenthesization is already limited by Bison's stack in such cases, anyway, so that the limit is probably fairly platform-independent. Patch originally by Gurjeet Singh, heavily revised by me
The PostgreSQL contrib tree
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This subtree contains porting tools, analysis utilities, and plug-in
features that are not part of the core PostgreSQL system, mainly
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