Have you had experience migrating between PostgreSQL and MS SQL Server?

Yes, migration experience between PostgreSQL and MS SQL Server exists, and it requires consideration of differences in architecture, data types, and SQL dialects.

Key points during migration:

• Data types: Some types in PostgreSQL have no direct equivalents in MS SQL and vice versa. For example, serial in PostgreSQL corresponds to IDENTITY in MS SQL.
• SQL syntax: Differences in functions, operators, and query structures require adaptation.
• Schema migration: Exporting the structure of tables, indexes, constraints, and recreating them in the target DBMS.
• Data: Exporting and importing data usually via CSV or specialized tools.
• Triggers and procedures: Rewritten considering the features of the target DBMS's procedural language.

To facilitate the process, migration tools can be used, for example:

• SQL Server Migration Assistant (SSMA) for PostgreSQL
• pgLoader — for migrating from MS SQL to PostgreSQL

Overall, migration requires careful planning, testing, and data integrity verification.