Missing PostgreSQL support migration:import

[josefglatz]

I've used the json export/import to migrate some tx_news_domain_model_news records from TYPO3 v12 (MySQL) to TYPO3 v13 (PostgreSQL). The export works like a charme. Thank you for the extension! Modifying all stuff within Listeners makes really sense. Thank you for your motivation @einpraegsam!

However, the usage of the import command in TYPO3 v13 with PostgreSQL results in errors. I put the quick fixes here as patch which targets 12.9.0. These may not be perfect and also not 100% comprehensive. However, the import worked with them.

in2code-migration-postgres-database-utility.patch
in2code-migration-postgres-import-quoting.patch

[josefglatz]

There are some more places.

E.G. when not excluding all tables

Empty INSERT INTO ... () VALUES () fails on PostgreSQL when target schema has no overlapping columns

migration:import crashes with a SQL syntax error on PostgreSQL targets whenever the JSON contains records for a table whose target-side schema shares no column names with the exported row. MySQL/MariaDB tolerate this as an "all
defaults" insert; PostgreSQL rejects it.

In inconsistence sys_file records

Default values on import are only possible with MySQl