The Catalog Hall - welcome back

Welcome @name to the Catalog Hall! This is the heart of my work - here we not only browse scrolls, but learn to choose them, name them and arrange them so that every catalog is as readable as a starry sky.

In the previous location you learned the simple order SELECT ... FROM .... Now we go deeper. You will master five arts of the catalog scribe:

What you will learn

• Choosing columns - when to take everything (

  *

  ) and when only the fields you need.
• Aliases (AS) - how to give a column a nicer name in the result.
• DISTINCT - how to draw out only the unique values, with no repetitions.
• ORDER BY - how to arrange scrolls ascending (

  ASC

  ) or descending (

  DESC

  ), even by several fields at once.
• LIMIT - how to limit the number of scrolls and how to paginate results (

  OFFSET

  ).

Our Library - a reminder of the shelves

We still work on the same

biblioteka

database:

| Shelf (table) | What it stores | |---------------|----------------| |

ksiazki

| title, author, category, year of publication, price, availability | |

autorzy

| first name, surname, country, year of birth | |

kategorie

| section names | |

czytelnicy

| first name, surname, e-mail, city, enrollment date | |

wypozyczenia

| who borrowed which book and when |

Take up the stylus, @name. It is time to turn a raw shelf into a beautiful, ordered catalog. Onward!