android - Query about sync database columns with days of the week -

i'm doing android studio project , i'm using sqlite database. in app allow user enter calorie intake day.

the database have corresponding columns hold users calorie intake day. mondays calorie intake saved in monday_cal column.

edit: app has 2 tables in database; 1 stores user details, calories needed , mon_cal etc. 2 stores product details , calories amount. user selects product , calories added total.

for example,

my question how make column in calories being entered change match days

ex:

when monday on column being selected changes monday_cal tuesday_cal.

my original plan simple if statement , presumed there call on (clock or calender) cant find material or tutorials on area think may searching wrong phrase? , if way not possible there other alternatives.

you don't want storing individual days fields in user table. if you're storing mon-sun, you're limiting ever keeping 7 days history per person.

a better solution separate calorie intake own table, related user table, this:

create table calorie_intake(   user_id integer not null,   intake_date date,   calories integer,   primary key(user_id, intake_date),   foreign key (user_id) references users(id) ); 

this schema uses id field of users table create relationship. find users calorie intake specific day execute query similar following:

select calories   users u     inner join calorie_intake       on u.id = i.user_id     u.id = 1       , intake_date = '2015-04-10'; 

which give calorie intake user id 1, on april 10th, 2015.

this process of creating relationships , moving away 'all data in 1 table' design called normalisation, there plenty of info out there on subject , if going doing database work @ all, shooting in foot not being aware of concept. heres link started