The missing INSERT
INSERT INTO AllowedTime(Dept, Room, Time) SELECT 'CSCI', 'RRO223', M.Time FROM MeetingTime M ;
SQL on the board
What was this about?
SELECT C1.Dept, C2.Dept, C1.MaxE FROM (SELECT F.inst, SUM(F.Enrollment*F.CH) as Fstudent FROM Course F WHERE F.CH > 0 GROUP BY F.inst) AS Fload, Course FX WHERE FX.inxt
This should be ok, but isn’t the same problem.
SELECT C.inst, SUM(C.Enrollment*C.CH) as CHG FROM Course C GROUP BY C.inst ORDER BY CHG DESC ;
This looks ok, but the inner SELECT
doesn’t add
anything.
SELECT FCHG.inst, FCHG.CHG FROM (SELECT C.inst, SUM(C.Enrollment*C.CH) as CHG FROM Course C GROUP BY C.inst) FCHG ;
This looks bad. FCHG
is an instance, not a table.
SELECT FCHG.inst, FCHG.CHG FROM (SELECT C.inst, SUM(C.Enrollment*C.CH) as CHG FROM Course C GROUP BY C.inst) FCHG WHERE FCHG.CHG > 0.9 * (SELECT MAX(F.CGH) FROM FCHG F) ;
This will probably work.
SELECT FCHG.inst, FCHG.CHG FROM (SELECT C.inst, SUM(C.Enrollment*C.CH) as CHG FROM Course C GROUP BY C.inst) FCHG, (SELECT MAX(SUM(C.Enrollment*C.CH)) as MaxCGH FROM Course C GROUP BY C.inst) MCHG WHERE FCHG.CHG > 0.9 * MCHG.MaxCGH ;
Middleware
C SQLite3 examples
The C/C++ interface to SQLite is described in An Introduction to the SQLite C/C++ Interface; however, you might want to start with the quickstart documentation.
- C example that only opens the database
- C example that does a lot of checking
- C example that lists pairs of friends
- C example that lists the friends of x
- C example with a callback
- Makefile for C examples
Python SQLite3 examples
These are documented in the
description
of the sqlite3
module.
It follows
Python’s
standard database API.
Java JDBC
This example uses several of the standard Java JDBC classes where are documented in on-line tutorials of the JDBC. Several JDBC classes were used.
These programs were first tested using the
sqlite-jdbc driver
of Taro Saito.
However because this library
does not support the
PreparedStatement
,
they were also tested using the MySQL JDBC driver.