Sql server statistics not updating
Statistics (hereafter called stats) are used by the query optimizer to find an acceptable execution plan for queries referencing specific columns.
With good stats, the optimizer can make informed decisions about these sorts of things: Correct decisions in these areas are dependent on accurate stats.
Without accurate statistics, indexes simply don’t work and good execution plans will not be created. These particular numbers describe the distribution of data in a column of a table or indexed view in a form that the optimizer can use.
Automatic creation depends on the database setting Auto Create Statistics being enabled.
This is the default and in most cases it should remain enabled.
Good stats can make the difference between a query that runs in less than a second or one that takes an hour to complete. When you create an index, a set of statistics for that index is also created. Stats created in this way are called, not surprisingly, ‘Index stats’ to differentiate them from ‘column stats’.
Column stats can be created automatically or manually.
The realization stunned me because data statistics are the basis for all query optimization.
Statistics are the foundation that indexes are built upon.