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Gevorderde SQL
Jasmin Ludolf
Data Science Content Developer, DataCamp
WHERE gebruiken met geaggregeerde functies
SELECT AVG(budget) AS avg_budget
FROM films
WHERE release_year >= 2010;
|avg_budget |
|--------------------|
|41072235.18324607...|
WHERE gebruiken met geaggregeerde functies
SELECT SUM(budget) AS sum_budget
FROM films
WHERE release_year = 2010;
|sum_budget|
|----------|
|8942365000|
SELECT MIN(budget) AS min_budget
FROM films
WHERE release_year = 2010;
|min_budget|
|----------|
|65000 |
WHERE gebruiken met geaggregeerde functies
SELECT MAX(budget) AS max_budget
FROM films
WHERE release_year = 2010;
|max_budget|
|----------|
|600000000 |
SELECT COUNT(budget) AS count_budget
FROM films
WHERE release_year = 2010;
|count_budget|
|------------|
|194 |
ROUND()
- Rond een getal af op een bepaald aantal decimalen
SELECT AVG(budget) AS avg_budget
FROM films
WHERE release_year >= 2010;
|avg_budget |
|--------------------|
|41072235.18324607...|
ROUND(number_to_round, decimal_places)
SELECT ROUND(AVG(budget), 2) AS avg_budget
FROM films
WHERE release_year >= 2010;
|avg_budget |
|-----------|
|41072235.18|
ROUND() naar een geheel getal
SELECT ROUND(AVG(budget)) AS avg_budget
FROM films
WHERE release_year >= 2010;
|avg_budget|
|----------|
|41072235 |
SELECT ROUND(AVG(budget), 0) AS avg_budget
FROM films
WHERE release_year >= 2010;
|avg_budget|
|----------|
|41072235 |
ROUND() met een negatieve parameter
SELECT ROUND(AVG(budget), -5) AS avg_budget
FROM films
WHERE release_year >= 2010;
|avg_budget|
|----------|
|41100000 |
- Alleen numerieke velden
Laten we oefenen!
Gevorderde SQL
