@see nette/database
Rozšíření API
Podmínka je připojena k LEFT JOIN klauzuli
...->left()
$selection = $context->table('book')
->left(':product_price.active', 1)
->select('book.*, :product_price.value');
SELECT book.*, product_price.value
FROM book
LEFT JOIN product_price ON book.id = product_price.book_id
AND (product_price.active = 1)
$selection = $context->table('book')
->left(':product_price.active', 1)
->where(':book_tag.tag.name LIKE', 'PHP')
->left(':product_price.value > ?', 0)
->left(':book_tag.tag_id IS NOT NULL')
->select('book.*, :product_price.value');
SELECT book.*, product_price.value FROM book
LEFT JOIN book_tag ON book.id = book_tag.book_id AND (book_tag.tag_id IS NOT NULL)
LEFT JOIN tag ON book_tag.tag_id = tag.id
LEFT JOIN product_price ON book.id = product_price.book_id AND (product_price.active = 1 AND product_price.value > 0)
WHERE (tag.name LIKE "PHP")
Podmínky lze libovolně míchat, jenom je třeba mít na paměti, že bude podmínka připojena k LEFT JOIN klauzuli podle prvního sloupečku v podmínce (obvykle je uveden jenom jeden, takže netřeba řešit).
$selection = $context->table('book')
->left(':product_price.active', 1)
->left(':book_tag.tag_id IS NOT NULL OR :product_price.active IS NOT NULL') // bude pripojeno k book_tag
->select('book.*, :product_price.value');
SELECT book.*, product_price.value FROM book
LEFT JOIN product_price ON book.id = product_price.book_id AND (product_price.active = 1)
LEFT JOIN book_tag ON book.id = book_tag.book_id AND (book_tag.tag_id IS NOT NULL OR product_price.active IS NOT NULL)
...->alias()
$selection = $context
->table('book')
->alias(':product_price', 'pp')
->left('pp.active', 1)
->select('book.*, pp.value');
SELECT book.*, pp.value
FROM book
LEFT JOIN product_price AS pp ON book.id = pp.book_id AND (pp.active = 1)
$selection = $context->table('book')
->alias(':product_price', 'pp')
->left('pp.active', 1)
->alias(':book_tag.tag', 't')
->where('t.name LIKE', 'PHP')
->left('pp.value > ?', 0)
->left(':book_tag.tag_id IS NOT NULL')
->select('book.*, pp.value');
SELECT book.*, pp.value FROM book
LEFT JOIN book_tag ON book.id = book_tag.book_id AND (book_tag.tag_id IS NOT NULL)
LEFT JOIN tag AS t ON book_tag.tag_id = t.id
LEFT JOIN product_price AS pp ON book.id = pp.book_id AND (pp.active = 1 AND pp.value > 0)
WHERE (t.name LIKE "PHP")
LEFT JOIN s aliasem, ale vybira se z ne-aliasovane
$selection = $context
->table('book')
->alias(':product_price', 'pp')
->left('pp.active', 1)
->select('book.*, :product_price.value');//tricky
SELECT book.*, product_price.value
FROM book
LEFT JOIN product_price AS pp ON book.id = pp.book_id AND (pp.active = 1)
LEFT JOIN product_price ON book.id = product_price.book_id
Stává se, že v subselectu je třeba použít alias tabulky, a s ním pracovat. Klasická Selection se snaží tento alias dohledat, což končí chybou:
...->where('author.id = (SELECT b.author_id FROM book AS b LIMIT 1)');
Řešením je použití vykřičníku před !b.author_id
, celé to vypadá:
$selection = $context->table('author')
->where('author.id = (SELECT !b.author_id FROM book AS b LIMIT 1)');
SELECT *
FROM author
WHERE (author.id = (SELECT b.author_id FROM book AS b LIMIT 1))
Stejně jako v SQL: Zajistí použití požadovaného indexu.
...->forceIndex()
$selection = $context->table('book')
->forceIndex('use_this_index')
->select('book.*');
SELECT book.* FROM book
FORCE INDEX (`use_this_index`)