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Comment by hamburglar | Hacker News Reader

The DSL for your database is called SQL.

This is a quip that misses the parent's point. SQL isn't very composable, because its syntax requires infix notation, position-dependent phrases, separators, and the like. The abstract syntax tree of SQL is much more valuable than its syntax, which is essentially just a bad English serialization that resembles a natural language sentence.

A DSL which manipulates queries and then produces syntactically valid SQL is tremendously valuable.

SQL is composable if you use views, just create a view for anything that you want to reuse in multiple queries.

Doesn't work because it completely screws up query optimization.

Maybe in some crappy RDBMSs, but not in Postgres.

If you encounter such an issue, there are ways around it:

https://www.red-gate.com/simple-talk/sql/performance/control...

For that I'd need to dynamically create such views, which requires a SQL generator anyway :)

Views are only half the answer. Try factoring out a set of conditions and use them both in a `select` and in `update`.

Also, views tend to pollute the namespace a bit: you want a set of descriptive names, per application, and possibly per application version. Schemata help here, though.

Bare in mind that SQL was designed to allow non-technical business users to use it. In most offices, a vetern business user or BI person will know how to use SQL. So SQL is a DSL for relational deconstructing of data models that is conceptually simple enough for people to grasp.

Templating can absolutely save time and boilerplate, but adding a DSL over a DSL in the form or ORM may well be the problem.

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