Syntax
Not all keywords are required
SELECT -- columns to show /*REQUIRED*/
FROM -- tables to use /*REQUIRED*/
WHERE -- rows to pick /*OPTIONAL*/
GROUP BY -- column to total /*OPTIONAL*/
HAVING -- totals to pick /*OPTIONAL*/
ORDER BY -- columns to sort /*OPTIONAL*/
DECLARE
Use DECLARE to declare a variable
DECLARE { @LOCAL_VARIABLE[AS] data_type [ = value]}
DECLARE @COURSE_ID AS INT = 5