+function engine:set_encoding() -- to UTF-8
+ local driver = self.params.driver;
+ if driver == "SQLite3" then
+ return self:transaction(function()
+ if self:select"PRAGMA encoding;"()[1] == "UTF-8" then
+ self.charset = "utf8";
+ end
+ end);
+ end
+ local set_names_query = "SET NAMES '%s';"
+ local charset = "utf8";
+ if driver == "MySQL" then
+ set_names_query = set_names_query:gsub(";$", " COLLATE 'utf8_bin';");
+ local ok, charsets = self:transaction(function()
+ return self:select"SELECT `CHARACTER_SET_NAME` FROM `CHARACTER_SETS` WHERE `CHARACTER_SET_NAME` LIKE 'utf8%' ORDER BY MAXLEN DESC LIMIT 1;";
+ end);
+ local row = ok and charsets();
+ charset = row and row[1] or charset;
+ end
+ self.charset = charset;
+ return self:transaction(function() return self:execute(set_names_query:format(charset)); end);
+end