How to multi-match two tables efficiently? The Next CEO of Stack Overflow

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How to multi-match two tables efficiently?



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I'm relatively new to database-design and want to create a SQLite database for an application. The application needs to handle lots of objects and assign them to a smaller list of categories. Both tables have multiple columns. The problem is, that every object may belong to an indefinite amount of categories and I need to query both efficiently: All objects that belong to a specific category and for any object to which categories it belongs, which is why I can't just use joins.



My idea was to create a third table with just two columns, matching objects to categories. But it looks like an ugly solution to me and I also don't know what indices I should set upon it, if any at all. I might end up with the key column's data being saved four times: In the original table, in its PRIMARY KEY, in the matching table, and in the index on that table.



Is there a better approach or maybe even a standard method to handle such situations?









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    I'm relatively new to database-design and want to create a SQLite database for an application. The application needs to handle lots of objects and assign them to a smaller list of categories. Both tables have multiple columns. The problem is, that every object may belong to an indefinite amount of categories and I need to query both efficiently: All objects that belong to a specific category and for any object to which categories it belongs, which is why I can't just use joins.



    My idea was to create a third table with just two columns, matching objects to categories. But it looks like an ugly solution to me and I also don't know what indices I should set upon it, if any at all. I might end up with the key column's data being saved four times: In the original table, in its PRIMARY KEY, in the matching table, and in the index on that table.



    Is there a better approach or maybe even a standard method to handle such situations?









    share







    New contributor




    Bachsau is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.























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      0








      I'm relatively new to database-design and want to create a SQLite database for an application. The application needs to handle lots of objects and assign them to a smaller list of categories. Both tables have multiple columns. The problem is, that every object may belong to an indefinite amount of categories and I need to query both efficiently: All objects that belong to a specific category and for any object to which categories it belongs, which is why I can't just use joins.



      My idea was to create a third table with just two columns, matching objects to categories. But it looks like an ugly solution to me and I also don't know what indices I should set upon it, if any at all. I might end up with the key column's data being saved four times: In the original table, in its PRIMARY KEY, in the matching table, and in the index on that table.



      Is there a better approach or maybe even a standard method to handle such situations?









      share







      New contributor




      Bachsau is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.












      I'm relatively new to database-design and want to create a SQLite database for an application. The application needs to handle lots of objects and assign them to a smaller list of categories. Both tables have multiple columns. The problem is, that every object may belong to an indefinite amount of categories and I need to query both efficiently: All objects that belong to a specific category and for any object to which categories it belongs, which is why I can't just use joins.



      My idea was to create a third table with just two columns, matching objects to categories. But it looks like an ugly solution to me and I also don't know what indices I should set upon it, if any at all. I might end up with the key column's data being saved four times: In the original table, in its PRIMARY KEY, in the matching table, and in the index on that table.



      Is there a better approach or maybe even a standard method to handle such situations?







      database-design sqlite





      share







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      Bachsau is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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      share







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      Bachsau is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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      share



      share






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