mysql - SQL - Check Availability -


i'm planning develop hotel management system each hotel has/have rate(s) particular set of days. rate values stored in table fine.

table below.

enter image description here

sql query use check whether there existing rates particular date range. 

select * `hotel_rate`   (from_date <= '2013-04-18' , to_date <= '2013-04-22') or (from_date >= '2013-04-18' , to_date >= '2013-04-22') or (from_date >= '2013-04-18' , to_date <= '2013-04-22') or (from_date <= '2013-04-18' , to_date >= '2013-04-22')

what i'm trying add rate date range '2013-04-18' '2013-04-22'. there added rates date range '2013-04-20' '2013-04-23'. want inform administrator who's adding rates rates has been applied particular period he/she has selected.

the problem sql query fetch rows database want particular row(s) rates overlapped. in example result set should contain row has id = 4.

given according knowledge before adding rate should check below 4 conditions. 2 black lines show existing rates hotel. yellow lines show possible overlapping scenarios. in given set 1st yellow line from_date 2nd yellow line to_date.

enter image description here how can fix ? how can overlapped rate row ?

i not quite sure if following, seems want determine if there records have kind of overlap 2 dates input. if case suggest this

select * `hotel_rate`   from_date between ? , ?   or to_date between ? , ?

here of course, ? 2 dates. needs happen have overlap either from_date record or to_date record fall between input dates (input dates inclusive).


Comments

Post a Comment

Popular posts from this blog

node.js - Bad Request - node js ajax post -

i'm using express 3.0 , node v0.11.0. have button submits form , i'm using ajax post data json object node server. client code is: $('#contact').submit(function(e) { console.log('submit called'); var formdata = json.stringify($('form').serializeobject()); console.log(formdata); $.ajax({ url: "http://localhost:3000/savedata/", type: "post", datatype: 'json', data: {objectdata: formdata}, contenttype: "application/json", complete: function() { console.log('process complete'); }, success: function(data) { console.log('process sucess'); }, error: function() { console.log('process error'); }, }); return false; }); then on server: var express = require('express'); var app = express(); app.set('views', __dirname + '/views'); app.set('view engine', 'jade'); app.use(express.bodyparser());...
Read more

Why does Ruby on Rails generate add a blank line to the end of a file? -

running rails generate controller foo home results in: class foocontroller < application controller def home end end (there's nothing on line in actual file, blank line) is there purpose blank line? it's common use newline indicate end of line, last line. many editors (like vi, use) add in newline silently. consensus text files (especially in unix world) should end in newline, , there have been problems historically if wasn't present. why should text files end newline? the tool used count lines in file "wc" counts newlines in file, without trailing newline show 3 instead of 4. it improves readability of templates used in generator. consider: https://github.com/rails/rails/blob/master/railties/lib/rails/generators/rails/controller/templates/controller.rb to remove trailing newline, template have last line of: end<% end -%> instead of: end <% end -%> that seems less readable me. the discussion below refers ...
Read more

keyboard - Smiles and long press feature in Android -

i've created android keyboard. how add features inserting smilies, , using long keypresses display symbols? to create long-press behavior allows select several options pop-up menu, follow guide (specifically pop-up menu section): http://developer.android.com/guide/topics/ui/menus.html smileys (also known emoticons) combination of keys, understood programs , parsed same way. have do, when clicks smiley face on keyboard, simulate pressing of key combination matching emoticon. example, when clicks smiley, should simulate key presses ':' , ')' :). here's list of emoticons: http://en.wikipedia.org/wiki/list_of_emoticons
Read more