sqlite> explain query plan select save_date from view_user where id= 1 ;
 0 | 0 |TABLE user AS u USING PRIMARY KEY
 1 | 1 |TABLE role AS r USING PRIMARY KEY

sqlite> explain select save_date from view_user where id= 1 ;
 0 |Trace| 0 | 0 | 0 || 00 |
 1 |Integer| 1 | 1 | 0 || 00 |
 2 |Goto| 0 | 16 | 0 || 00 |
 3 |OpenRead| 1 | 797 | 0 | 34 | 00 |
 4 |OpenRead| 2 | 2 | 0 | 4 | 00 |
 5 |MustBeInt| 1 | 13 | 0 || 00 |
 6 |NotExists| 1 | 13 | 1 || 00 |
 7 |Column| 1 | 3 | 2 | 0 | 00 |
 8 |MustBeInt| 2 | 13 | 0 || 00 |
 9 |NotExists| 2 | 13 | 2 || 00 |
 10 |Column| 1 | 1 | 3 || 00 |
 11 |RealAffinity| 3 | 0 | 0 || 00 |
 12 |ResultRow| 3 | 1 | 0 || 00 |
 13 |Close| 1 | 0 | 0 || 00 |
 14 |Close| 2 | 0 | 0 || 00 |
 15 |Halt| 0 | 0 | 0 || 00 |
 16 |Transaction| 0 | 0 | 0 || 00 |
 17 |VerifyCookie| 0 | 109 | 0 || 00 |
 18 |TableLock| 0 | 797 | 0 |user| 00 |
 19 |TableLock| 0 | 2 | 0 |role| 00 |
 20 |Goto| 0 | 3 | 0 || 00 |