Page-Level Compression

Page-level compression is an implementation of true data compression, using both column prefix and dictionary-based compression. Data is compressed be storing repeating values or common prefixes only once and then referencing those values from other columns and rows. When you implement page compression for a table, row compression is applied as well. Page-level compression offers increased data compression over row-level compression alone but at the expense of greater CPU utilization. It works using these techniques:

• First, row-level data compression is applied to fit as many rows as it can on a single page.

• Next, column prefix compression is run. Essentially, repeating patterns of data at the beginning of the values ...

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