Fix miscellaneous issues with Microsoft SQL Server

pysqlsync/dialect/mssql/connection.py

@@ -42,6 +42,8 @@ def open(self) -> BaseContext:
             "PWD": self.params.password,
             "TrustServerCertificate": "yes",
         }
+        if self.params.database is not None:
+            params["DATABASE"] = self.params.database
         conn_string = ";".join(
             f"{key}={value}" for key, value in params.items() if value is not None
         )

pysqlsync/dialect/mssql/mutation.py

@@ -1,3 +1,4 @@
+import typing
 from typing import Optional
 
 from pysqlsync.formation.mutation import Mutator
@@ -8,7 +9,8 @@
     Table,
     join_or_none,
 )
-from pysqlsync.model.id_types import LocalId
+
+from .object_types import MSSQLColumn
 
 
 class MSSQLMutator(Mutator):
@@ -37,7 +39,7 @@ def mutate_table_stmt(self, source: Table, target: Table) -> Optional[str]:
             if source_def == target_def:
                 continue
 
-            name = LocalId(f"df_{source_column.name.local_id}")
+            name = typing.cast(MSSQLColumn, source_column).default_constraint_name()
             if source_def is not None:
                 constraints.append(f"DROP CONSTRAINT {name}")
             if target_def is not None:

pysqlsync/dialect/mssql/object_types.py

@@ -1,3 +1,4 @@
+import typing
 from typing import Optional
 
 from pysqlsync.formation.object_types import (
@@ -10,14 +11,38 @@
 )
 from pysqlsync.model.data_types import quote
 from pysqlsync.model.id_types import LocalId
+from pysqlsync.util.typing import override
 
 
 class MSSQLColumn(Column):
+    def default_constraint_name(self) -> LocalId:
+        "The name of the constraint for DEFAULT."
+
+        return LocalId(f"df_{self.name.local_id}")
+
     @property
     def data_spec(self) -> str:
         nullable = " NOT NULL" if not self.nullable else ""
+        name = self.default_constraint_name()
+        default = (
+            f" CONSTRAINT {name} DEFAULT {self.default}"
+            if self.default is not None
+            else ""
+        )
         identity = " IDENTITY" if self.identity else ""
-        return f"{self.data_type}{nullable}{identity}"
+        return f"{self.data_type}{nullable}{default}{identity}"
+
+    @override
+    def create_stmt(self) -> str:
+        return f"ADD {self.column_spec}"
+
+    @override
+    def drop_stmt(self) -> str:
+        if self.default is not None:
+            name = self.default_constraint_name()
+            return f"DROP CONSTRAINT {name}, COLUMN {self.name}"
+        else:
+            return f"DROP COLUMN {self.name}"
 
 
 class MSSQLTable(Table):
@@ -28,39 +53,16 @@ def alter_table_stmt(self, statements: list[str]) -> str:
 
     def add_constraints_stmt(self) -> Optional[str]:
         statements: list[str] = []
-
-        constraints: list[str] = []
-        for column in self.columns.values():
-            if column.default is None:
-                continue
-            name = LocalId(f"df_{column.name.local_id}")
-            constraints.append(
-                f"ADD CONSTRAINT {name} DEFAULT {column.default} FOR {column.name}"
-            )
-        if constraints:
-            statements.append(self.alter_table_stmt(constraints))
-
         if self.table_constraints:
             statements.append(
                 f"ALTER TABLE {self.name} ADD\n"
                 + ",\n".join(f"CONSTRAINT {c.spec}" for c in self.table_constraints)
                 + ";"
             )
-
         return join_or_none(statements)
 
     def drop_constraints_stmt(self) -> Optional[str]:
         statements: list[str] = []
-
-        constraints: list[str] = []
-        for column in self.columns.values():
-            if column.default is None:
-                continue
-            name = LocalId(f"df_{column.name.local_id}")
-            constraints.append(f"DROP CONSTRAINT {name}")
-        if constraints:
-            statements.append(self.alter_table_stmt(constraints))
-
         if self.table_constraints:
             statements.append(
                 f"ALTER TABLE {self.name} DROP\n"

pysqlsync/formation/object_types.py

@@ -203,9 +203,13 @@ def data_spec(self) -> str:
         return f"{self.data_type}{nullable}{default}{identity}"
 
     def create_stmt(self) -> str:
+        "Creates a column as part of an ALTER TABLE statement."
+
         return f"ADD COLUMN {self.column_spec}"
 
     def drop_stmt(self) -> str:
+        "Removes a column as part of an ALTER TABLE statement."
+
         return f"DROP COLUMN {self.name}"
 
     def soft_drop_stmt(self) -> str:

tests/test_generator.py

@@ -130,18 +130,13 @@ def test_create_default_numeric_table(self) -> None:
             tables.DefaultNumericTable,
             'CREATE TABLE "DefaultNumericTable" (\n'
             '"id" bigint NOT NULL,\n'
-            '"integer_8" smallint NOT NULL,\n'
-            '"integer_16" smallint NOT NULL,\n'
-            '"integer_32" integer NOT NULL,\n'
-            '"integer_64" bigint NOT NULL,\n'
-            '"integer" bigint NOT NULL,\n'
+            '"integer_8" smallint NOT NULL CONSTRAINT "df_integer_8" DEFAULT 127,\n'
+            '"integer_16" smallint NOT NULL CONSTRAINT "df_integer_16" DEFAULT 32767,\n'
+            '"integer_32" integer NOT NULL CONSTRAINT "df_integer_32" DEFAULT 2147483647,\n'
+            '"integer_64" bigint NOT NULL CONSTRAINT "df_integer_64" DEFAULT 0,\n'
+            '"integer" bigint NOT NULL CONSTRAINT "df_integer" DEFAULT 23,\n'
             'CONSTRAINT "pk_DefaultNumericTable" PRIMARY KEY ("id")\n'
-            ");\n"
-            'ALTER TABLE "DefaultNumericTable" ADD CONSTRAINT "df_integer_8" DEFAULT 127 FOR "integer_8";\n'
-            'ALTER TABLE "DefaultNumericTable" ADD CONSTRAINT "df_integer_16" DEFAULT 32767 FOR "integer_16";\n'
-            'ALTER TABLE "DefaultNumericTable" ADD CONSTRAINT "df_integer_32" DEFAULT 2147483647 FOR "integer_32";\n'
-            'ALTER TABLE "DefaultNumericTable" ADD CONSTRAINT "df_integer_64" DEFAULT 0 FOR "integer_64";\n'
-            'ALTER TABLE "DefaultNumericTable" ADD CONSTRAINT "df_integer" DEFAULT 23 FOR "integer";',
+            ");",
         )
 
     def test_create_fixed_precision_float_table(self) -> None:
@@ -291,10 +286,9 @@ def test_create_default_datetime_table(self) -> None:
             tables.DefaultDateTimeTable,
             'CREATE TABLE "DefaultDateTimeTable" (\n'
             '"id" bigint NOT NULL,\n'
-            """"iso_date_time" datetime2 NOT NULL,\n"""
+            """"iso_date_time" datetime2 NOT NULL CONSTRAINT "df_iso_date_time" DEFAULT '1989-10-24 23:59:59',\n"""
             'CONSTRAINT "pk_DefaultDateTimeTable" PRIMARY KEY ("id")\n'
-            ");\n"
-            """ALTER TABLE "DefaultDateTimeTable" ADD CONSTRAINT "df_iso_date_time" DEFAULT '1989-10-24 23:59:59' FOR "iso_date_time";""",
+            ");",
         )
 
     def test_create_enum_table(self) -> None: