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SQL średnio zaawansowany

Jasmin Ludolf

Data Science Content Developer, DataCamp

Użycie WHERE z funkcjami agregującymi

SELECT AVG(budget) AS avg_budget
FROM films
WHERE release_year >= 2010;
|avg_budget          |
|--------------------|
|41072235.18324607...|
SQL średnio zaawansowany

Użycie WHERE z funkcjami agregującymi

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     |
SQL średnio zaawansowany

Użycie WHERE z funkcjami agregującymi

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         |
SQL średnio zaawansowany

ROUND()

  • Zaokrągla liczbę do podanej liczby miejsc dziesiętnych
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|
SQL średnio zaawansowany

ROUND() do liczby całkowitej

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  |
SQL średnio zaawansowany

ROUND() z ujemnym parametrem

SELECT ROUND(AVG(budget), -5) AS avg_budget
FROM films
WHERE release_year >= 2010;
|avg_budget|
|----------|
|41100000  |
  • Tylko pola numeryczne
SQL średnio zaawansowany

Czas na ćwiczenia!

SQL średnio zaawansowany

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