fix in mysql

migrations/mysql/0030_document_utf8mb4.sql

@@ -0,0 +1,8 @@
+-- Existing MySQL databases may have inherited utf8mb3 from the database default.
+-- Convert all persisted document text to utf8mb4 so emoji and other 4-byte
+-- Unicode characters can be stored in both current documents and revisions.
+ALTER TABLE pads CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
+ALTER TABLE revisions CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
+ALTER TABLE workspaces CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
+ALTER TABLE notes CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
+ALTER TABLE note_revisions CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

migrations/postgres/0030_document_utf8mb4.sql

@@ -0,0 +1,2 @@
+-- PostgreSQL text values are already stored as UTF-8.
+SELECT 1;

migrations/sqlite/0030_document_utf8mb4.sql

@@ -0,0 +1,2 @@
+-- SQLite TEXT values already support full Unicode.
+SELECT 1;