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

Answer 1

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 2

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 3

• 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 4

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 5

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 6

-- 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.