PostgreSQL with Npgsql and Dapper: NpgsqlDataSource, Type Mapping, COPY and LISTEN/NOTIFY
From .NET you connect to PostgreSQL through a single NpgsqlDataSource for the whole application; only UTC values can be written to timestamptz, yet Dapper can silently shift a DateTime with an unspecified Kind by three hours. DI and pool defaults, = ANY(@ids), DateOnly and jsonb, Dapper sending enums as integers, Execute, NpgsqlBatch and binary COPY on 100,000 rows, automatic preparation, cache invalidation with LISTEN/NOTIFY and OpenTelemetry.
14 Nov 2026
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10 min
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4
