Database schema:

CREATE TABLE divisions (
	division TEXT NOT NULL -- example: ['D1', 'B1'],
	name TEXT -- example: ['Division 1A', 'Bundesliga'],
	country TEXT -- example: ['Deutschland', 'Belgium'],
	PRIMARY KEY (division)
)


CREATE TABLE matchs (
	"Div" TEXT -- example: ['D1', 'B1'],
	"Date" DATE -- example: ['2020-08-08', '2020-08-09'],
	"HomeTeam" TEXT -- example: ['Antwerp', 'Club Brugge'],
	"AwayTeam" TEXT -- example: ['Mouscron', 'Charleroi'],
	"FTHG" INTEGER -- example: ['0', '1'],
	"FTAG" INTEGER -- example: ['0', '1'],
	"FTR" TEXT -- example: ['A', 'D'],
	season INTEGER -- example: ['2020', '2021'],
	CONSTRAINT fk_matchs_divisions FOREIGN KEY("Div") REFERENCES divisions (division)
)

Question: How many Eredivisie teams have played in 2008?
Evidence: Eredivisie is the name of division; 2008 refers to season; teams refer to HomeTeam;

SQL:
SELECT COUNT(DISTINCT T1.HomeTeam) FROM matchs AS T1 INNER JOIN divisions AS T2 ON T1.Div = T2.division WHERE T2.name = 'Eredivisie' AND T1.season = 2008