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This could be enforced in the schema via triggers and/or security permissions. Cooperation from the client is not required. EDIT: Oracle has append-only tabl

This could be enforced in the schema via triggers and/or security permissions. Cooperation from the client is not required. EDIT: Oracle has append-only tables, and can also use "blockchain" to verify integrity. See the IMMUTABLE option on CREATE TABLE[0]. PostgreSQL doesn't appear to have append-only tables, so using security and/or triggers seems to be the only option there. [0] https://docs.oracle.com/en/database/oracle/oracle-database/23/sqlrf/CREATE-TABLE.html https://docs.oracle.com/en/database/oracle/oracle-database/2...

jacques_chester 2y ago
You're correct, I overlooked triggers. Though that may be a bridge too far for some folks, triggers are only really comfortable for folks who are deep on RDBMSes. For lots of app developers the ORM is the limit of the world.
- Mister_Snuggles 2y ago
  ORMs could offer a unique advantage by allowing the user to describe an append-only table and generating the required triggers (or the appropriate CREATE TABLE options). They'd also be able to include helpers to make working with the table easier - like defaulting to selecting current rows only, or an easy way to specify that you want rows as-of a certain point in time. I'm not sure if any ORMs actually support this though.
  - refset 2y ago
    I suspect there have been a great many examples and attempts at the ORM level - this one with "bi-temporal chaining" springs to mind: https://github.com/goldmansachs/reladomo https://github.com/goldmansachs/reladomo And without the ORM layer there's this extension for Postgres: https://github.com/hettie-d/pg_bitemporal https://github.com/hettie-d/pg_bitemporal
  - codr7 2y ago
    My "ORM" supports event sourcing, or at least easily plugging it in at the model level. https://github.com/codr7/hostr/blob/532295b40dcad6c54082e1d3c9d992321208496f/src/Hostr/Domain/Model.cs#L26 https://github.com/codr7/hostr/blob/532295b40dcad6c54082e1d3...
mike_hearn 2y ago
More to the point Oracle has flashback queries: SELECT ... AS OF <timestamp or logical clock time> So you can query the database as of any point in the past, making manual work to implement the same feature with custom columns redundant. Oracle can also show you a record of transactions made and what SQL to run to undo them, including dependency tracking between transactions.
- fulafel 2y ago
  This sounds like proprietary syntax for SQL 2011 temporal queries. Apparently supported by eg MS SQL server and MariaDB.

jacques_chester 2y ago

You're correct, I overlooked triggers. Though that may be a bridge too far for some folks, triggers are only really comfortable for folks who are deep on RDBMSes. For lots of app developers the ORM is the limit of the world.

Mister_Snuggles 2y ago
ORMs could offer a unique advantage by allowing the user to describe an append-only table and generating the required triggers (or the appropriate CREATE TABLE options). They'd also be able to include helpers to make working with the table easier - like defaulting to selecting current rows only, or an easy way to specify that you want rows as-of a certain point in time. I'm not sure if any ORMs actually support this though.
- refset 2y ago
  I suspect there have been a great many examples and attempts at the ORM level - this one with "bi-temporal chaining" springs to mind: https://github.com/goldmansachs/reladomo https://github.com/goldmansachs/reladomo And without the ORM layer there's this extension for Postgres: https://github.com/hettie-d/pg_bitemporal https://github.com/hettie-d/pg_bitemporal
- codr7 2y ago
  My "ORM" supports event sourcing, or at least easily plugging it in at the model level. https://github.com/codr7/hostr/blob/532295b40dcad6c54082e1d3c9d992321208496f/src/Hostr/Domain/Model.cs#L26 https://github.com/codr7/hostr/blob/532295b40dcad6c54082e1d3...

mike_hearn 2y ago

More to the point Oracle has flashback queries: SELECT ... AS OF <timestamp or logical clock time> So you can query the database as of any point in the past, making manual work to implement the same feature with custom columns redundant. Oracle can also show you a record of transactions made and what SQL to run to undo them, including dependency tracking between transactions.

fulafel 2y ago
This sounds like proprietary syntax for SQL 2011 temporal queries. Apparently supported by eg MS SQL server and MariaDB.