On Thu, 16 Jan 2025 09:41:35 -0800 Jeff Davis <pg...@j-davis.com> wrote:
> On Thu, 2025-01-16 at 14:53 +0900, Yugo NAGATA wrote: > > Instead of generating complete patterns considering every case- > > varying characters, > > two clauses considering only the first case-varying character are > > generated. > > Did you consider other approaches that integrate more deeply into the > indexing infrastructure? This feels almost like a skip scan, which > Petter Geoghegan is working on. If you model the disjunctions as skips, > and provide the right API that the index AM can use, then there would > be no limit. > > For example: > > start scanning at '123FOO' > when you encounter '123FOP' skip to '123FOo' > continue scanning > when you encounter '123FOp' skip to '123FoO' > ... That seems true there is similarity between ILIKE search and skip scan, although, on my understand, skip scan is for multi-column indexes rather than text. I have no concrete idea how the infrastructure for skip scan to improve ILIKE, anyway. > Also, I'm working on better Unicode support to handle multiple case > variants in patterns. For instance, the Greek letter Sigma has three > case variants (one upper and two lower). What's the right API so that > the index AM knows which case variants will sort first, so that the > skips don't go backward? That seems true there is similarity between ILIKE search and skip scan, although, on my understand, skip scan is for multi-column indexes rather than text. I have no concrete idea how the infrastructure for skip scan to improve ILIKE, anyway. > Also, I'm working on better Unicode support to handle multiple case > variants in patterns. For instance, the Greek letter Sigma has three > case variants (one upper and two lower). What's the right API so that > the index AM knows which case variants will sort first, so that the > skips don't go backward? I don't have idea for handling letters with multiple case variants in my patch, either. I overlooked such pattern at all. So, I'll withdraw the proposal, for now. Regards, Yugo Nagata -- Yugo NAGATA <nag...@sraoss.co.jp>
