在 mysql 命令行客户端中检查追踪可以通过 pager less 命令（或你所在操作平台的等效命令）来简化。另一种方法是将追踪发送到文件，就像这里展示的那样：Examining a trace in the mysql command-line client can be made less difficult using the pager less command (or your operating platform's equivalent). An alternative can be to send the trace to a file, similarly to what is shown here:

SELECT TRACE INTO DUMPFILE file
FROM INFORMATION_SCHEMA.OPTIMIZER_TRACE;

然后，你可以将此文件传递给支持 JSON 的文本编辑器或其他查看器，例如 适用于 Firefox 和 Chrome 的 JsonView 插件，它可以彩色显示对象，并允许展开或折叠对象。You can then pass this file to a JSON-aware text editor or other viewer, such as the JsonView add-on for Firefox and Chrome, which shows objects in color and allows objects to be expanded or collapsed.

INTO DUMPFILE 比 INTO OUTFILE 更适合此用途，因为后者会转义换行符。如前所述，执行 end_markers_in_json 语句时，应确保 OFF 为 SELECT INTO，以确保输出是有效的 JSON。INTO DUMPFILE is preferable to INTO OUTFILE for this purpose, since the latter escapes newlines. As noted previously, you should ensure that end_markers_in_json is OFFwhen executing the SELECT INTO statement, so that the output is valid JSON.