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GEswin

Search a litle bit in this forum , advantages are a lot.. Imagine a table with 10.000 records.. and you only need some of them.. TTable will fetch all (Inncesary traffic over lan/wan, increases pc memory use, loads mysql etc).. with TMyQuery you only select what you need, faster, less memory, less traffic.. this plus other advantages like doing join's, union, etc.

GEswin

If it's connecting to the database, check this:

http://dev.mysql.com/doc/refman/5.1/en/dns.html

Add the skip-name-resolve to your my.ini/cnf

If it's when opening the query (you're already connected), then look at the amount of data fetched. If you select all fields and only need a few ones, then adjust your query to retrieve only data you need. Retrieving big blobs also takes its time, sometimes it's better to get blobs only when you need them.

Regards

GEswin

It should be:

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Datamodule1.Update_Case.sql.add('UPDATE casemaster SET survey_date1 = curdate(), surveyor1 =' + QuotedStr(sys.currentuser));

QuotedStr add's Quotes to text (") so SQL knows it's a string.

Best way anyway would be:

Code: Select all

Datamodule1.Update_Case.sql.Clear;
Datamodule1.Update_Case.sql.add('UPDATE casemaster SET survey_date1 = curdate(), surveyor1 = :surveyor1');
Datamodule1.Update_Case.sql.add('where inventory.casemaster.autoid = :autoid' );
Datamodule1.Update_Case.ParamByName('surveyor1').AsString := sys.currentuser;
Datamodule1.Update_Case.ParamByName('autoid').AsString := CaseMasterid.text;
Datamodule1.Update_Case.Execute;

Where second example you only need to set SQL once, and then everytime you need to update, just fill the params and execute query.

GEswin

Best is not to use reserved words as field/table/view etc names. Have a look at http://dev.mysql.com/doc/refman/5.0/en/ ... words.html to know which ones are reserved. This will avoid you a lot of problems

GEswin

Code: Select all

 Params.ParamByName('ABlobField').LoadFromFile(....);

 or

 Params.ParamByName('ABlobField').LoadFromStream(...);

would do the job.

GEswin

Code: Select all

QryStorico.SQLInsert.Add('INSERT INTO storico(COD_STOR, DESC_STATO, MOTIVO_STATO) VALUES (:COD_STOR, DESC_STATO, :MOTIVO_STATO)');

The WHERE part of the INSERT isn't valid. You can't use a WHERE in an INSERT statment. The rest looks well.

Regards

GEswin

Antaeus is right. Also specify when you get exactly this problem (sql sentence, operation...) to get more specific help.

GEswin

Well, TMyQuery lets you drill-down data to what you need, you can also join tables etc. If you have for example a 1000 records, and you only need to show 5 records which have some common reference, then with a TMyQuery you just select those 5 (example select * from table where condition = xxx), and it would retrieve only those records from server, with TMyTable everything is retreived and then procesed locally. But best to know about why to use TMyQuery would be knowing SQL.

GEswin

Perhaps TClientDataSet is a solution.

GEswin

Do you have multiple connections set ??

GEswin

Set compress option to true at the TMyConnection is first thing to change to speedup over WAN. Other issues are basically optimize query's, just select the minimal information that you need (If for example you have a table with 20 fields, and only need 3, select only those 3), also drill down the number of rows returned to the value you really need (Make as much as you can with querys instead of local delphi code). Other more advanced tricks are setting up for example a local replication server (Data is replicated to another server that can be on the other side of WAN), for this i recommend taking a look at mysql website.

Regards

GEswin

I don't know if MAX_ALLOWED_PACKET 1GB is a valid value, but i'm sure with MAX_ALLOWED_PACKET = 16MB will work.

GEswin

Has it got a primary key ? Is this key in the select statement ??

GEswin

You should at least post the error message you're getting. You'll know the last inserted ID with mytable.LastInsertID.

GEswin

Well, firewalling is a good idea, and if remote users have fixed ip, only allow those IP's... Also a good option is when creating mysql users/priveleges to just allow each user just touch the needed database/tables.

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