How to setup MySQL table to follow a variable over time? -

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say have several registered users in website.

users saved on single table 'users' assigns unique id each 1 of them.

i want allow users track expenses, miles driven, temperature, etc.

i can't sure each user enter value all trackable variables when login -- example of happen be:

'example data' user     date         amount    miles     temp    etc 1        3/1/2010     $10.00    5         54 2        3/1/2010     $20.00    15           1        3/12/2010              5         55 1        3/15/2010    $10.00    25        51 3        3/20/2010                        45 3        4/12/2010    $20.00    10        54

what best way set tables situation?

should create table exclusive each user when register? (could end thousands of user-exclusive tables)

'user-1 table' date         amount    miles     temp    etc 3/1/2010     $10.00    5         54 3/12/2010              5         55 3/15/2010    $10.00    25        51  'user-3 table' date         amount    miles     temp    etc 3/20/2010                        45 4/12/2010    $20.00    10        54  , on...

should create single table same example data above? (could end gigantic table needs combed find rows requested user id's).

'user data table' user     date         amount    miles     temp    etc 1        3/1/2010     $10.00    5         54 2        3/1/2010     $20.00    15           1        3/12/2010              5         55 1        3/15/2010    $10.00    25        51 3        3/20/2010                        45 3        4/12/2010    $20.00    10        54

any suggestions?

databases built handle similar data set together.

what want single user-data-table, multiple users in same table split user_id. might want further normalize though, stores:

user     date         type      units 1        3/1/2010     dollars   10.00 1        3/1/2010     miles     5 1        3/1/2010     temp      54 2        3/1/2010     dollars   20.00 2        3/1/2010     miles     15           1        3/12/2010    miles     5 1        3/12/2010    temp      55 etc

or further if user+date makes specific trip

trip-table tripid    user     date ========= ======== ========= 1         1        3/1/2010  type-table typeid    description ========= ============ 1         dollars 2         miles etc  trip-data tripid     type      units =========  ========  ======= 1          1         10.00 1          2         5 etc

however, if (or always) show data in form entered, data pivoted on input columns (like spreadsheet), better off sticking un-normalised form brevity, programmability , performance.

could end gigantic table needs combed find rows requested user id's

assuming employ indexes , judiciously, modern rdbms built handle gigantic amounts of data. indexes allow queries seek data needs, there little penalty in keeping in 1 table.


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