The result of the above SQL statement will be the number 3, because the customer Smith has made 3 orders in total. If you don't specify a WHERE clause when using COUNT, your statement will simply return the total number of rows in the table, which in our case is 7:
Uses of Sleep Spindles Edit. Sleep spindles are one of several measures employed by the brain to keep a sleeper in an unconscious state. This pattern is produced during sleep to inhibit the processing of unnecessary information, which would especially interrupt stage 2 sleep.
Stage 2 sleep is characterized by the presence of: 1  Sleep spindles: 12- to 14-Hz waves during a burst that lasts at least half a second.  K-complex: a sharp wave associated with temporary inhibition of neuronal firing.