68 lines
807 B
Markdown
68 lines
807 B
Markdown
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# SparQL
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> [!NOTE]
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> Resources taken from [this website](https://sparql.dev/)
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## SQL Queries
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### SELECT
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```SQL
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SELECT ?var1, ?var2, ...
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```
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### WHERE
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```SQL
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WHERE {
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pattern1 .
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pattern2 .
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...
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}
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```
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### FILTER
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It's used to restrict [`WHERE`](#where) clauses
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```SQL
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WHERE {
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?person <http://example.com/hasCar> ?car .
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FILTER (?car = <http://example.com/Car1>)
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}
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```
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### OPTIONAL
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It's used to fetch available content if exists
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```SQL
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SELECT ?person ?car
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WHERE {
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?person <http://example.com/hasCar> ?car .
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OPTIONAL {
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?car <http://example.com/hasColor> ?color .
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}
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}
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```
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### LIMIT
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Limits results
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```SQL
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LIMIT 10 -- Take only 10 results
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```
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## SparQL functions
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### COUNT
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```SQL
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SELECT (COUNT(?person) AS ?count)
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WHERE {
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?person <http://example.com/hasCar> ?car .
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}
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```
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