3/10/2023 0 Comments Bulk copy logYou can move DWG objects and their attributes to a variety of geospatial formats and, in some cases, move the data back into AutoCAD drawings. SQL Server has three recovery models: Full, Simple, and Bulk-Logged. Bulk copy transfers features from one data store to another. A minimally logged bulk copy can be performed if all of these conditions are met. Let’s create a links table that has a URL and name, but just use numbers with generate_series as the values.Ĭreating a normal logged table like this and inserting 10 million items takes around 33 seconds on my laptop. You can use Bulk Copy to copy data from one feature source to another, either in the same format or in a different one. ![]() So combining UNLOGGED tables, RETURNING *, with the intention of inserting items in bulk, we can insert 10 million rows in a simple SQL statement. ![]() The returning clause will return the selected rows from a query, all fields with returning *, whether it’s an update or in this case a DELETE query. UNLOGGED tables are normal tables, but with an UNLOGGED option supplied at creation time. In the article How to test UNLOGGED tables for performance in PostgreSQL they demonstrate how the database can be shutdown and truncate an UNLOGGED table. Creating a table as unlogged and skipping the WAL process means rows can generally be inserted at a higher rate, but with the possibility of data loss if the database crashes or shuts down without a full shutdown. But there is a trade-off.Īctivity for normal tables is logged to the write-ahead log (WAL). If you need to roll back all or part of the bulk copy when an error occurs, you can use a SqlBulkCopy-managed transaction, perform the bulk copy operation within an existing transaction, or be enlisted in a System.Transactions Transaction. By using UNLOGGED tables we can insert rows at a higher rate compared with a normal table. The bulk copy operation occurs in a non-transacted way, with no opportunity for rolling it back.
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