Address casemapping issues in sqlite/mysql

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+# How to modify Anope sqlite databases
+
+Anope uses a custom SQLiite function (anope_canonicalize) for canonicalizing strings for case insensitivity comparisons.
+It does this by using SQLites support for having indexes on expressions https://www.sqlite.org/expridx.html.
+
+For example the account table could look like:
+
+```
+CREATE TABLE `anope_db_account` (
+	`display`,
+	`pass`,
+	`email`,
+	`language`,
+	`id` NOT NULL PRIMARY KEY,
+	FOREIGN KEY (id) REFERENCES anope_db_objects(id) ON DELETE CASCADE DEFERRABLE INITIALLY DEFERRED
+);
+CREATE INDEX idx_display ON `anope_db_account` (anope_canonicalize(display));
+```
+
+So, to do a SELECT which utilizes the indicies, Anope does something like:
+
+```
+SELECT id FROM `anope_db_account` WHERE anope_canonicalize(display) = anope_canonicalize('Adam');
+```
+
+If you are using your own SQLite instance, like the sqlite command line interface, the anope_canonicalize function
+will be missing. To fix this load one of libanope_sqlite_ascii.so, libanope_sqlite_rfc1459_inspircd.so,
+or libanope_sqlite_rfc1459.so into SQLite, depending on your casemap configuration.
+
+```
+sqlite> .load lib/libanope_sqlite_ascii.so
+```