Can a table in SQL have multiple columns as foreign keys that refer only to one primary key of another table? - Quora
![qgis - What does "PostgreSQL layer has no primary key." when loading layer from database manager mean? - Geographic Information Systems Stack Exchange qgis - What does "PostgreSQL layer has no primary key." when loading layer from database manager mean? - Geographic Information Systems Stack Exchange](https://i.stack.imgur.com/Yn4tX.png)
qgis - What does "PostgreSQL layer has no primary key." when loading layer from database manager mean? - Geographic Information Systems Stack Exchange
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