sql - Database Programming Concepts -

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So I have read some books on SQL and I have used SQL and created a database, but in fact anything upgraded There is no pair tables, one pair, this kind of thing.

So now I am working on a project which is very big. There are several tables in the database and we will process 40 to 1000 to 80'000 rows of data.

Now I lack a few basic SQL concepts myself, for example:

I have a dataset with datasets and file descriptions. The files are listed in a table and file details are listed in the other. We also have a build table and a fourth table that comes together in the build table, file table and file description table.

Like the problems, "How do I work on files and the correct file descriptions are associated with associated files and build?

Even my university has I did not cover and now I feel that I am out of my depth.

We take another example, file table. In my application, I have 40'000 files, add me those files Which are not already present in the file table. Or do I have to search and add each individual entry if it does not exist and if it is not, leave it?

So my real question is, where is a good place to read general concepts On this topic, I found that the best books, which is the Selco's "SQL for Smarteries" series.

They represent different data structures in SQL In the manner of generalization, the fundamentals introduced are:


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