Moving from SQL Server to PostgreSQL — often to cut licensing costs — starts with the schema. The two engines are closer than MySQL and PostgreSQL in some ways, but their type systems, identity handling, and object qualification still diverge enough to trip up a manual migration.
Identity columns
SQL Server's IDENTITY(1,1) maps to PostgreSQL's GENERATED … AS IDENTITY or a SERIAL-backed sequence. A schema diff recognises identity columns and emits the PostgreSQL form rather than copying the T-SQL syntax.
Type differences
NVARCHAR/NCHAR→varchar/text(PostgreSQL text is Unicode by default).DATETIME2→timestamp;BIT→boolean.UNIQUEIDENTIFIER→uuid.MONEY→numeric.
Schema qualification
SQL Server objects are qualified as schema.object (commonly dbo). PostgreSQL uses schemas too, but the default is public. Foreign keys and views referencing dbo.Table must be requalified to the target schema — a good diff tool does this automatically.
What needs manual review
Stored procedures, functions, and triggers are written in T-SQL and will not run on PostgreSQL's PL/pgSQL without a rewrite. Views can often be adapted but should be reviewed. A cross-dialect tool flags these up front so they do not surprise you mid-migration.
Compare, then migrate
Point a schema diff at your SQL Server database and the PostgreSQL target to generate the structural DDL, then handle procedural objects as a checklist. FoxSchema supports both dialects (plus Azure SQL). Get started.
