BLOB data is a field that holds large amounts of data per record. This data can be either in a text format or a binary format. When working with BLOB data in SQL Server, the amount of data per record is typically well beyond the 8K of data that can fit within a single record.
There are various data types used for storing BLOB data and they've changed over time. The data types available for BLOB storage have been static for many years, but in SQL Server 2005, Microsoft introduced many new data types.
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