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Comment by scwoodal | Hacker News Reader

What are the common use cases for this scenario?

Table prefixes? Running more than one instance of an application in a single database. You'll find it's supported in most php apps and frameworks. Wordpress, Drupal, Laravel, Magento, etc.

Not just php either. Ruby/Rails Active Record, for example, supports it.

And I imagine dynamic, variable bound table names are probably in every ORM in just about every language.

Variable table names can also be useful if you have poor man's partitioning – separate tables with historical data , like "logs_201610", "logs_201611", "logs_201612", etc.

Another scenario I just thought of: your schema is more or less dynamic. For example, Drupal lets developers/site administrators create entities with custom fields, each field gets its own DB table, and to load an entity you need to

    SELECT * FROM node
    LEFT OUTER JOIN field_data_field_name_1 ON .. 
    LEFT OUTER JOIN field_data_field_name_2 ON ..
    ...

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