So let's say you inherited an SQLITE3 database that has just one table like so:
CREATE TABLE data (id integer, name text)
And it looks like so:
------- DATA -------
89074352 red
12344112 red
47298489 blue
34444333 blue
23453245 red
10000001 yellow
...
--------------------
So the text elements and very redundant. And imagine that the text elements are huge instead of just one word. You would want to avoid that by making a new table that contains every text element only once. The final state of the database would have two tables that look like this:
CREATE TABLE text_keys ("key" integer primary key autoincrement, "name" text not null)
------- TEXT_KEYS -------
1 red
2 blue
3 yellow
...
-------------------------
CREATE TABLE data ("id" integer, "key" integer references text_keys)
------- DATA -------
89074352 1
12344112 1
47298489 2
34444333 2
23453245 1
10000001 3
...
--------------------
What commands would you type in SQLITE3 to go from the first state to the final state of the database ? I've made some research, but have not been able to solve this one.
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