el hilo que recorre cada peldaño
a reading log
19 peldaños
01 · make a place to put it
a table, and the columns it holds
primera vez que escribes
( ) , ;02 · put something in it
a row, and the text around it
primera vez que escribes
'03 · ask for it back
selecting columns, and all of them
primera vez que escribes
*04 · only the ones you want
a condition on the rows
primera vez que escribes
< >05 · a note to yourself
a comment
primera vez que escribes
-06 · in an order that helps
sorting, both ways
nada nuevo que alcanzar
07 · give it a better name
matching exactly, and renaming
primera vez que escribes
= _08 · titles that look alike
a pattern instead of an exact match
primera vez que escribes
%09 · anything but that one
not equal, written the SQL way
nada nuevo que alcanzar
10 · stick two things together
joining text end to end
primera vez que escribes
|11 · count them up
totals over every row
nada nuevo que alcanzar
12 · a second place to put things
another table, to point at the first
nada nuevo que alcanzar
13 · two tables at once
a join, and the dotted names it needs
primera vez que escribes
.14 · one row for each person
grouping, so each name appears once
nada nuevo que alcanzar
15 · only some of the groups
a condition on the groups themselves
nada nuevo que alcanzar
16 · when there is nothing to match
keeping the row anyway
nada nuevo que alcanzar
17 · change what is there
updating a row in place
primera vez que escribes
+18 · take it out again
deleting, and checking what is left
nada nuevo que alcanzar
19 · the whole thing
everything so far, answering one question
nada nuevo que alcanzar