On 14 Dec 2009, at 8:52am, Florian Schricker wrote: >>> Primary keys are Oper, Product, Category, Name and CreateTS >> There is only one primary key per table. > > So to say the primary key is "Oper, Product, Category, Name, CreateTS".
No. Go read a boos on databases. The shorter your primary key is, the faster everything works. You want a very short primary key. There would be no point in putting 'CreateTS' in your primary key unless it's possible for two records to exist which have the same "Oper, Product, Category, Name" but different CreateTS. I might guess that your primary key is probably just Product. If it's not possible to have two records with the same 'Product' then that is your primary key. >> I urge you to learn about database design and SQL. >> [snip] Step back and do some learning before >> you dig a big hole and fall into it. > > I need to get things running quickly. The advice is sound. You cannot just guess at this thing and magically do it right. For instance, a badly chosen primary key can completely mess up your entire database, giving it duplicate entries or having entries mysteriously disappear for no obvious reason. You have given your own example of why you should read a book or two before you start. > > Works fine - thank you. I chose a similar, see below. > >> From: Simon Slavin <slav...@bigfraud.org> > >>> - CreateTS (Timestamp) > >> No such type in SQLite. Take a look at > > Ok this one seems to be some problem with me vs SQLite. I got the > create clause for the table from somebody else inside my company (some > DB2 guy) which is > > CREATE TABLE MEASURE ( > [...] > "CREATETS" TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP, > [...] Yes. DB2 has different field types to SQLite. And MySQL, Progres, Oracle, and all other database engines each have different field types. When converting a project from one to another you have to study what you have to change. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
