On 02/24/2015 08:53 PM, Igor Tandetnik wrote: > On 2/24/2015 8:42 PM, russ lyttle wrote: >> The 'a' table defines spaces to be controlled, the 'b' tables the >> control schedules and parameters. >> It would not be unreasonable to assume the 'a' table has >100 rows. >> Each row in the 'a' table is associated with 3 'b' tables, all the names >> known in advance and created off line at the same time as the row in the >> 'a' table. >> Each 'b' table has up to 1,440 rows. > > Replace these three tables with a single table, holding three times as > many rows. It would have an extra column holding the "original source" > indicator - a value that indicates which of the three tables this row > originated from. Now, in table "a" store this indicator where you > planned to store the table name.
Thanks for the input. To eliminate the need to reference a table would require combining 300 tables into one table. A user editing entries for one space could crash the whole system. That's basically what happened aboard the Yorktown in 1997. A cook trying to enter an item into the lunch menu killed the engines on the ship. It's beginning to look like the 'b' table should be broken into a separate db and the 'a' table have indicators as to which table in b.db to use. If there were an sqlite3 sketch for arduino, that would work better than my original plan. Each space could have its own copy of the tables it is to use. Lots of database management and communications problems go away. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 473 bytes Desc: OpenPGP digital signature URL: <http://mailinglists.sqlite.org/cgi-bin/mailman/private/sqlite-users/attachments/20150225/6e08d46f/attachment.pgp>
