Sams Teach Yourself Transact-SQL in 21 Days, Second Edition

Managing BLOB Data

Depending on whether the BLOB data is stored in the data row or outside of the data row, the way you manage it will be different. When BLOB strings are stored in the data row, reading and writing the data strings can be as fast as reading and writing character and binary strings. SQL Server does not have to access separate pages of data to read or write the BLOB string. Unless the 'text in row' option is specified, BLOB strings are stored outside the data row with only the text pointers to these strings in the data row. These text pointers point to the pages that contain the string fragments that contain the actual BLOB data in multiple pages, as discussed earlier in this lesson.

Using the Large Object System Functions

Whenever ...