Discussion of article "SQLite: Native handling of SQL databases in MQL5" - page 5
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Exactly. Artem, you have done it with MQL, but the topic is about SQLite. Even your library would be simpler and more "high-speed" if it used SQLite databases. I was not talking about the absence or impossibility of doing it. I was talking about the simplicity of the solution.
Well, how much simpler than what I have done - just request the necessary data in your programme, and for both platforms. But the topic is really not about that. So let's drop the flud.
From the article, albeit with difficulty, I understand this example
This query selects records with a value greater than 15000 from the database. Another example there was to select the sum... But I, for example, need to select the least/most value from the database. Or the sum of values greater than/less than zero. I think there is such a possibility, but there is not enough information in the form of MQL5 documentation. Pulling from examples is difficult for me. But if I don't have it... if necessary, I will try to figure it out.
You need to learn the language of SQL queries. This article shows how to use them with the help of these MQL5 functions and gives some examples of SQL queries.
The task "to make a help on SQL" was not set. There are many tutorials and courses on this topic.
You need to learn the SQL query language. This article shows how to use them with the help of these MQL5 functions and gives some examples of SQL queries.
The task of "making a SQL help" was not set. There are many tutorials and courses on this topic.
Yes Rashid, I have searched and found what can be found in Russian. But agree, if you offer to use something, then the description should be available without additional searches. Plus, I have already said that the form of documentation is more acceptable to me as MQL documentation. And all that I found in the network on SQLite somehow difficult for my understanding. But this is not relevant for me.
Further I expressed a little bit realised opinion.
Forum on trading, automated trading systems and testing trading strategies.
Discussion of the article "SQLite: native work with SQL databases in MQL5".
Alexey Viktorov, 2020.05.16 10:26 AM
After a closer, but still superficial, familiarisation with the capabilities of SQLite, I came to the conclusion that in this form, sorry, it is only a rattle.
In order to use the unconditional advantages of SQLite it would be useful to have a history database, at least. And better, a database of current positions and pending orders. I hope that at the MT level the creation of such databases will not take much time. Especially if the tables, as they are now, can be formed from SQLite database. This approach will definitely simplify the work with the history of orders and deals. It will be very easy to get the amounts of swap, commissions, profit on all deals with one position ID or for a certain period.
Recently I read in one of the topics that the history selection is based on the opening time, but correctly on the closing time.... Having a SQLite database removes such questions. By what criterion you want to use and select it. But few programmers will create these bases for themselves. IMHO.
Exactly few programmers will write database filling to take advantage of new toys. And Artyom was immediately indignant, "how is it not available", take the library and use it. But in his library everything is done by MQL means, and SQLite remains a rattle.
I wonder how difficult it is to replace the existing algorithm of filling the history and the list of open positions and pending orders with filling the SQLite database and then converting it to the current form. And how it will affect the speed of MT.
Just imagine how easy it will be to collect all orders and trades by position ID, whether open or already closed.....
Yes, Rashid, I searched and found what I could find in Russian. But agree, if you offer to use something, the description should be available without additional searches. Plus, I have already said that the form of documentation is more acceptable to me as MQL documentation. And all that I found in the network on SQLite somehow difficult for my understanding. But this is not relevant for me.
We disagree.
Widely known systems have a lot of available documentation. Be realistic.
We disagree.
Widely known systems have plenty of documentation available. Be realistic.
I'm not insisting. This is just my subjective, possibly erroneous opinion.
Exactly few programmers will write database fills to take advantage of the new toys.
A script to create/update a database table from account history/instrument history is written in a few minutes.
The terminal most likely stores it all in the same DBs, but they are unlikely to be directly accessed. And there is no sense in duplicating it into a castum database "out of the box".
A script to create/update a DB table from account history/instrument history is written in minutes.....
The terminal most likely stores all this in the same databases, but they are unlikely to give direct access to them. And there is no sense in duplicating it into a castum database "out of the box".
Yeah. I didn't think about security. Probably because there are no fraudulent thoughts:))))))) I agree. I take back my words.
@Rashid Umarov I'm re-reading the article for the umpteenth time and each time I'm struck by a typo.
Please correct it and delete this message.
Fixed it in 2 places - strange typo. Thank you
Good afternoon!
When running the script DatabaseRead.mq5 - I do not create a database file at all (company.sqlite).
It does not generate any errors. The file is there, but I do not see it!
Can you help me to understand?