Junção de dados no SQL
Maham Faisal Khan
Senior Content Developer, DataCamp
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UNION
recebe duas tabelas como entrada e retorna todos os registros das duas tabelas.
UNION ALL
pega duas tabelas e retorna todos os registros das duas, incluindo repetições.
SELECT *
FROM left_table
UNION
SELECT *
FROM right_table;
SELECT *
FROM left_table
UNION ALL
SELECT *
FROM right_table;
.
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SELECT *
FROM monarchs;
| country | continent | monarch |
|----------------|-------------|-------------------------|
| Brunei | Asia | Hassanal Bolkiah |
| Oman | Asia | Haitham bin Tarik |
| Norway | Europe | Harald V |
| United Kingdom | Europe | Charles III |
SELECT monarch AS leader, country
FROM monarchs
UNION
SELECT prime_minister, country
FROM prime_ministers
ORDER BY country, leader
LIMIT 10;
|-------------------------|----------------|
| leader | country |
|-------------------------|----------------|
| Anthony Albanese | Australia |
| Hassanal Bolkiah | Brunei |
| Mostafa Madbouly | Egypt |
| Narendra Modi | India |
| Christopher Luxon | New Zealand |
| Harald V | Norway |
| Jonas Gahr Støre | Norway |
| Haitham bin Tarik | Oman |
| Shehbaz Sharif | Pakistan |
| Luís Montenegro | Portugal |
|-------------------------|----------------|
SELECT monarch AS leader, country
FROM monarchs
UNION ALL
SELECT prime_minister, country
FROM prime_ministers
ORDER BY leader, country
LIMIT 10;
| leader | country |
|-------------------------|----------------|
| Anthony Albanese | Australia |
| Hassanal Bolkiah | Brunei |
| Hassanal Bolkiah | Brunei |
| Mostafa Madbouly | Egypt |
| Narendra Modi | India |
| Christopher Luxon | New Zealand |
| Harald V | Norway |
| Jonas Gahr Støre | Norway |
| Haitham bin Tarik | Oman |
| Haitham bin Tarik | Oman |
Junção de dados no SQL