2011/8/4 Ammar Yasir ayax88@gmail.com:
On Thu, Aug 4, 2011 at 5:01 PM, Piotr Przybylski piotr.prz@gmail.com wrote:
2011/8/4 Marc Delisle marc@infomarc.info:
Piotr Przybylski a écrit :
2011/8/4 Ammar Yasir ayax88@gmail.com:
On Thu, Aug 4, 2011 at 2:01 AM, Marc Delisle marc@infomarc.info wrote:
Ammar Yasir a écrit : > > On Wed, Jul 27, 2011 at 10:22 PM, Ammar Yasir > <ammaryasir.88@gmail.com > mailto:ammaryasir.88@gmail.com> wrote: > > > > On Wed, Jul 27, 2011 at 3:37 PM, Marc Delisle > <marc@infomarc.info > mailto:marc@infomarc.info> wrote: > > Ammar, > With Firebug I had a look at the network traffic when I > click a > data > point to edit it: I was surprised to see none. > > IMO this is not good: it means that all the columns for all > rows > are in > memory, making the browser able to handle far less rows. > > Is there a reason why you are reading the complete rows to > generate the > plot? I expected that you would just read the necessary > columns, > then > use AJAX to read a complete row when the user wants to edit > it. > > I'm currently working on the edit feature for strings. I'll work > on > it after this. > > -- > > Implemented this and pushed to my repo. I only send the xField, > yField > and dataLabel to the user now. Ammar, you have reduced the amount of data transferred between the PHP level and the Javascript level, by sending less data in the querydata div.
Can you also reduce what is transferred between the MySQL server and the web server, by avoiding to generate "SELECT *" in the query generation part, instead selecting only the needed columns?
That would have been the ideal case but to generate the unique-condition( function PMA_getUniqueCondition($handle, $fields_cnt, $fields_meta, $row, $force_unique=false) ), I need the complete row. So I cannot do much about the query generation on the server side other than putting a limit on the number of rows retrieved.
It will increase complexity o bit but you can do one of the two:
- select one full row with "SELECT * FROM ... LIMIT 1" (any full row
will do so no ORDER here) and analyze which rows you need by looking for primary/unique key fields,
- if you have only one table you can analyze SHOW CREATE TABLE
statement and look for PRIMARY KEY and UNIQUE constraints
But PMA_getUniqueCondition() also handles the case when there is no unique key.
Yes, but in most cases there is one. If there is no unique key then 'SELECT *' is needed, but if there is one then the built query can return smaller result, without useless columns.
I actually had started my implementation like piotr has described but came across the PMA_getUniqueCondition() function later so went ahead with using that. The server side load can be acceptable I guess compared to what I transfer to the Javascript level ?
I believe it is acceptable. The only use case in which it makes difference is when you have large LOB columns in the table and are buffering MySQL response (using PMA_DBI_QUERY_STORE instead of PMA_DBI_QUERY_UNBUFFERED or cache'ing result in any way), because then you can very quickly get out of memory.