Question

I have a hotel booking system, when the user chooses the start date and end date for staying in the hotel, I want to give the total price:

For example: when the user chooses Start date: 2013-08-01, to : 2013-08-11 (two season default, and high season) also the price of days is different.

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This is my table:

How can write a SQL command (MySQL) or do I need to use PHP code?

Answer 1

Your data structure is not set up to do this very efficiently. However, it is still possible.

I would start by splitting out each date of the stay separately. Join this to the rates table. Then use a big case statement based on day of the week to get the rate. If there is no match in the rate table, then use the default rate:

select sum(case when dayname(thedate) = 'Monday' then coalesce(r.MonPrice, def.MonPrice)
                when dayname(thedate) = 'Tuesday' then coalesce(r.TuePrice, def.TuePrice)
                . . .
                when dayname(thedate) = 'Sunday' then coalesce(r.SunPrice, def.SunPrice) as TotalPrice
from (select strtodate('2013-08-01', '%Y-%m-%d') as thedate union all
      select strtodate('2013-08-02', '%Y-%m-%d') union all
      . . . 
      select strtodate('2013-08-11', '%Y-%m-%d')
     ) dates left outer join
     Rates r
     on dates.thedate between r.date_to and r.date_from cross join
     Rates def
     on def.season_price = 'default'

In this example, I’ve the dates are each put into a subquery. There are other ways to do this, but since you are constructing the query in php, this might be the easiest solution.

The “…” mean to add similar SQL code, since “…” is not recognized as part of SQL.