What are the steps to process a single SELECT statement?Steps
a. The select statement is broken into logical units
b. A sequence tree is built based on the keywords and expressions in the form of the logical units.
c. Query optimizer checks for various permutations and combinations to figure out the fastest way using minimum resources to access the source tables. The best found way is called as an execution plan.
d. Relational engine executes the plan and processes the data
What are the steps to process a single SELECT statement?SQL Server uses the following steps to process a single SELECT statement:
1. The parser breaks SELECT statement into logical units, such as keywords, expressions, operators, and identifiers.
2. A query tree is built.
3. The query optimizer then determines the best steps that can return fastest result while consuming the fewest resources.
4. The relational engine begins executing the execution plan, requesting the storage engine to pass up data.
5. The relational engine processes the data returned from the storage engine into the result set format and returns the result set to the client.