Database connectivity Delphi

Question

I'm using delphi for years, but never for database stuff, but recently started researching and testing.

I must say, i'm impressed, most of things happens automatically, i'm used to write by hand in php and python.

i'm going to develop a commercial system for a friend, (2 layers) 5 user computers, 1 database server.

Database server will be a decent machine with (raid-1) 2 hard drives running (MySql5.1 or Postgre or Firebird, open to suggestions).

ADO

• Easy to use
• Easy deployment (only mysqlconnector installer)
• The slower?

DbExpress

• Need to ship 4 files [dbxconnections.ini, dbxdrivers.ini, mysqldll, driverdll]
• The more complex (harder to use)
• ClientDataSet add complexity, but looks really useful
• No free Postgre driver?

Zeos

• Easy deployment (1 dll)
• Easy to use

As you can see the desired features are:

• fast
• easy to use
• easy to deploy

I can't test all in a real scenario (clients, server), so i hope that you guys with experience can help me out in which one to choose and why.

EDIT: Thanks everyone, i think i will go with ADO (probably) or Zeos

Thanks in advance
Arthur

Answer 1

@arthurprs, for you scenario

(2 layers) 5 user computers, 1 > database server.

The Firebird RDBMS is a very good option , because is very stable, fast, runs on Linux, Windows, and a variety of Unix platforms and meet with you requirements.

Respect to the components for connection i go for ZEOS.

I have used this combination in many small and medium projects, with excellent results.

Answer 2

id have to say im rather happy with NexusDB but the cost for the client/server versions might not be worth it.

it works client/server or fully embedded, simple enough you can have both in your app and switch between them, depending on your clients needs

• the embedded DB is free,
• client/server "Priced per developer" is AU$ 500
• No cost per install.

Oh yeh and its written in delphi ;)

Answer 3

I have worked on many commercial high volume systems using ADO without any problems. Deployment is relatively simple since its included in the OS. Since it has such a wide audience, most of the major issues have been identified and corrected. Getting help with ADO connectivity is very easy. The database support is very deep (connectionstrings.com) which make supporting additional database engines almost trivial (you may need to still install the client drivers, but that would be the same for almost any solution).

Performance isn't much of an issue, it really will come down to database architecture and engine selection.

Answer 4

I'd say to go with Firebird - is the most used database engine in the Delphi land (see here). For connectivity perhaps is better to go with Zeos (free) or DBX (if you can afford the Architect version - the only one who has the Firebird driver in it).

About ADO: Mature connectivity layer but it will be (forever - most probably) tied to Windows while Delphi will go cross-platform. Also, yes, it tend to be the slower one because of many reasons, including the ODBC drivers which are used in certain situations. But in your case, of course, as skamradt says, I don't think that it will matter so much.

Answer 5

Although I have read people not liking the idea of mixing the two, I have had good results using ADO Datasets as a "provider layer" which then feeds the data into TClientDataSets - so there's no reason you can't use ClientDataSets if you go down the ADO route if you find you need them (and they are useful).

Otherwise, I would echo the comment that ADO is a tried, trusted mechanism that isn't going anywhere. I've always found it more than fast enough. And configuration using UDL files is nice and easy.

Answer 6

• dbGo (ADO) is more simple to manage, more universal, more slow
• dbExpress is more fast, more complex to manage, supports less DBMS's
• ZeosDBO is simple to manage, universal like dbExp, slow like dbGo, cross-platform, has few additional components, all sources are accessible

There are few other libraries, resolving all above doubts, although all of them are commercial products. But there I am biased :)

Answer 7

We have used postgreSQL using Devart pg components with great success in medium sized database apps. We did some limited benchmarking with this combination and found it 2-3 x the speed of using ADO etc.

Answer 8

-- Data access components

I too favour the combination of TClientDataset and ADO. Had worked with it in past and I can say it's trustful. The flexibility of TClientDataset is a big gain. DBExpress is good too. Actually, I use clientdatasets with pretty much any data access layer that have an TDataset descendant...

-- Server

Firebird. Free and easily usable from OLEDB (I used with ODBC) and DBExpress (D2010+ have native DBX driver) - don't know ZEOS, but I believe that it also connect to FB. Scale well to many connections and big databases. There are databases on Firebird with 500Gb and many users reported.