From efcea3a80da7c4479d5fe168435ecc9fd06bdc72 Mon Sep 17 00:00:00 2001
From: John Turner <jturner.usa@gmail.com>
Date: Sun, 14 Sep 2025 00:16:10 -0400
Subject: Squashed 'subprojects/boost-sqlite/' content from commit 3378e35

git-subtree-dir: subprojects/boost-sqlite
git-subtree-split: 3378e353705271e569cf4ba15c467b840a39798c
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 doc/reference/collation.adoc | 45 ++++++++++++++++++++++++++++++++++++++++++++
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+== `sqlite/collation.hpp`
+[#collation]
+
+A https://www.sqlite.org/datatype3.html#collation[collation] is a comparison operator between two string-like values,
+that allows ordering with a custom algorithm.
+
+.Definition
+[source,cpp]
+----
+
+// Create a collation
+template<typename Func>
+void create_collation(connection & conn, cstring_ref name, Func && func);
+template<typename Func>
+void create_collation(connection & conn, cstring_ref name, Func && func, system::error_code &ec);
+
+// Delete an existing collation.
+void delete_collation(connection & conn, cstring_ref name, system::error_code & ec);
+void delete_collation(connection & conn, cstring_ref name);
+----
+
+ conn:: A connection to the database in which to install the collation.
+ name:: The name of the collation.
+ func:: The function
+
+The function must be callable with two `string_view` and return an int, indicating the comparison results.
+
+.Example
+[source,cpp]
+----
+// a case insensitive string omparison, e.g. from boost.urls
+int ci_compare(string_view s0, string_view s1) noexcept;
+
+extern sqlite::connection conn;
+
+// Register the collation
+sqlite::create_collation(conn, "iequal", &ci_compare);
+
+// use the collation to get by name, case insensitively
+conn.query("select first_name, last_name from people where first_name = 'Klemens' collate iequal;");
+
+// order by names case insensitively
+conn.query("select * from people order by last_name collate iequal asc;");
+----
+
-- 
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