MySQL Workbench查询统计信息：服务器和客户端计时？

Question

I'm running queries from the MySQL Workbench and it allows you to see the stats for each query. Part of these stats are "Timing (as measured at the client side)" and "Timing (as measured by the server side)". I've included an example of what this output looks like.

Timing stats from MySQL Workbench

I'm wondering why the timing on the server side is longer than on the client side. I may be completely wrong but I thought that the client side takes into account server time and a latency until the information is outputted, which would make the time measured by the client side longer.

I'm new to this and not very familiar with execution timing but the workbench manual didn't offer much help and assumed I already understood what the values meant and how they worked. Any help is appreciated!

Answer 1

I can't confirm this with documentation but running a quick test on a really large query and playing with the number of rows returned to the client results grid provided a possible insight:

Dont Limit:

Timing (as measured at client side): Execution time: 0:00:0.77752995

Timing (as measured by the server): Execution time: 0:00:7.46805535

Table lock wait time: 0:00:0.00018100

Duration / Fetch time in "Action Output" pane: 0.778s / 7.723 sec

10 Rows

Timing (as measured at client side): Execution time: 0:00:0.38576984

Timing (as measured by the server): Execution time: 0:00:0.00058682

Table lock wait time: 0:00:0.00018400

Duration / Fetch in "Action Output" pane: 0.386 / 0.00002 sec

It just makes sense to me that the server measures from the time the client started asking for records to the time it stopped, and the client measures the time it takes the server to generate the number of records it needs. Perhaps to return an "accurate" execution time is to set the rows to return to "No Limit" and check the "Duration" in the "Action Output" pane.

I've posted on the MySQL forum, hoping to get an explanation, will post back here if forthcoming.