sql - What is the precedence of multiple JOIN statements in sqlite? -


निम्न दो प्रश्न अलग-अलग परिणाम लौट रहे हैं, मुझे आश्चर्य है: 

  SELECT * FROM Foo JOIN बार बार पर bar.id = foo.bar_id baz.id = foo.baz_id पर जुड़ें zig.foo_id = foo.id;

और:

<पूर्व> SELECT * foo LEFT JOIN zig ON zig.foo_id = foo.id पर जोड़ें बार बार.आईडी = foo.bar_id JOZ baz पर baz.id = foo.baz_id;

मैं सोच रहा हूं कि जब आप LEFT JOIN पर zig , तब से कोई फर्क नहीं पड़ेगा क्योंकि मैं बार और baz में शामिल होने के समय zig के कॉलम। हालांकि, ऐसा प्रतीत होता है कि बाद में, जोन -के का बार और baz उस पंक्ति को निगलता है जहां zig null मान थे ... ऐसा क्यों है?

यह ठीक काम करता है । मैं गलत था।


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