Efcore.pg: 3.0.1 error while migrating

[yohsii]

while migrating, through code or package manager console, i get:
Object reference not set to an instance of an object.
here's the console output:

PM> update-database -context PuckContext
Microsoft.EntityFrameworkCore.Infrastructure[10403]
      Entity Framework Core 3.0.0 initialized 'PuckContext' using provider 'Npgsql.EntityFrameworkCore.PostgreSQL' with options: None
Microsoft.EntityFrameworkCore.Database.Command[20100]
      Executing DbCommand [Parameters=[], CommandType='Text', CommandTimeout='30']
      SELECT EXISTS (SELECT 1 FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n ON n.oid=c.relnamespace WHERE c.relname='__EFMigrationsHistory');
Executing DbCommand [Parameters=[], CommandType='Text', CommandTimeout='30']
SELECT EXISTS (SELECT 1 FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n ON n.oid=c.relnamespace WHERE c.relname='__EFMigrationsHistory');
Executing DbCommand [Parameters=[], CommandType='Text', CommandTimeout='30']
SELECT EXISTS (SELECT 1 FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n ON n.oid=c.relnamespace WHERE c.relname='__EFMigrationsHistory');
Microsoft.EntityFrameworkCore.Database.Command[20100]
      Executing DbCommand [Parameters=[], CommandType='Text', CommandTimeout='30']
      SELECT EXISTS (SELECT 1 FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n ON n.oid=c.relnamespace WHERE c.relname='__EFMigrationsHistory');
Executing DbCommand [Parameters=[], CommandType='Text', CommandTimeout='30']
SELECT "MigrationId", "ProductVersion"
FROM "__EFMigrationsHistory"
ORDER BY "MigrationId";
Microsoft.EntityFrameworkCore.Database.Command[20100]
      Executing DbCommand [Parameters=[], CommandType='Text', CommandTimeout='30']
      SELECT "MigrationId", "ProductVersion"
      FROM "__EFMigrationsHistory"
      ORDER BY "MigrationId";
Microsoft.EntityFrameworkCore.Migrations[20402]
      Applying migration '20190909191322_initial'.
Applying migration '20190909191322_initial'.
System.NullReferenceException: Object reference not set to an instance of an object.
   at Microsoft.EntityFrameworkCore.Migrations.MigrationsSqlGenerator.GetColumnType(String schema, String table, String name, ColumnOperation operation, IModel model)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Migrations.NpgsqlMigrationsSqlGenerator.ColumnDefinition(String schema, String table, String name, ColumnOperation operation, IModel model, MigrationCommandListBuilder builder)
   at Microsoft.EntityFrameworkCore.Migrations.MigrationsSqlGenerator.ColumnDefinition(AddColumnOperation operation, IModel model, MigrationCommandListBuilder builder)
   at Microsoft.EntityFrameworkCore.Migrations.MigrationsSqlGenerator.CreateTableColumns(CreateTableOperation operation, IModel model, MigrationCommandListBuilder builder)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Migrations.NpgsqlMigrationsSqlGenerator.Generate(CreateTableOperation operation, IModel model, MigrationCommandListBuilder builder, Boolean terminate)
   at Microsoft.EntityFrameworkCore.Migrations.MigrationsSqlGenerator.<>c.<.cctor>b__71_11(MigrationsSqlGenerator g, MigrationOperation o, IModel m, MigrationCommandListBuilder b)
   at Microsoft.EntityFrameworkCore.Migrations.MigrationsSqlGenerator.Generate(MigrationOperation operation, IModel model, MigrationCommandListBuilder builder)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Migrations.NpgsqlMigrationsSqlGenerator.Generate(MigrationOperation operation, IModel model, MigrationCommandListBuilder builder)
   at Microsoft.EntityFrameworkCore.Migrations.MigrationsSqlGenerator.Generate(IReadOnlyList`1 operations, IModel model)
   at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.GenerateUpSql(Migration migration)
   at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.<>c__DisplayClass15_2.<GetMigrationCommandLists>b__2()
   at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.Migrate(String targetMigration)
   at Microsoft.EntityFrameworkCore.Design.Internal.MigrationsOperations.UpdateDatabase(String targetMigration, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.UpdateDatabaseImpl(String targetMigration, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.UpdateDatabase.<>c__DisplayClass0_0.<.ctor>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)
Object reference not set to an instance of an object.

[yohsii]

potentially unsupported column type? since it seems to error here:
at Microsoft.EntityFrameworkCore.Migrations.MigrationsSqlGenerator.GetColumnType(String schema, String table, String name, ColumnOperation operation, IModel model)

[yohsii]

aah, the issue was that i hadn't deleted the initial migrations created for SQL Server.

now that i have, i created an initial migration using the postgres provider and tried to migrate but got this error:

Microsoft.EntityFrameworkCore.Infrastructure[10403]
      Entity Framework Core 3.0.0 initialized 'PuckContext' using provider 'Npgsql.EntityFrameworkCore.PostgreSQL' with options: None
System.ArgumentException: Keyword not supported: user (Parameter 'keyword')
   at Npgsql.NpgsqlConnectionStringBuilder.GetProperty(String keyword)
   at Npgsql.NpgsqlConnectionStringBuilder.set_Item(String keyword, Object value)
   at System.Data.Common.DbConnectionStringBuilder.set_ConnectionString(String value)
   at Npgsql.NpgsqlConnectionStringBuilder..ctor(String connectionString)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Storage.Internal.NpgsqlDatabaseCreator.Exists()
   at Microsoft.EntityFrameworkCore.Migrations.HistoryRepository.Exists()
   at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.Migrate(String targetMigration)
   at Microsoft.EntityFrameworkCore.Design.Internal.MigrationsOperations.UpdateDatabase(String targetMigration, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.UpdateDatabaseImpl(String targetMigration, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.UpdateDatabase.<>c__DisplayClass0_0.<.ctor>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)
Keyword not supported: user (Parameter 'keyword')