Overview
The basic compilation "pipeline" for a single query appears in Figure 8-1.
Figure 8-1. Query processor pipeline
When a query is compiled, the SQL statement is first parsed into an equivalent tree representation. For queries with valid SQL syntax, the next stage performs a series of validation steps on the query, generally called binding, where the columns and tables in the tree are compared to database metadata to make sure that those columns and tables exist and are visible to the current user. This stage also performs semantic checks on the query to make sure it is valid, such as making sure that the columns bound to a GROUP BY operation ...
Get Microsoft® SQL Server® 2008 Internals now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
