sqlite - How to find a gap in range in SQL -

-

this question explains how find first "unused" number in table, how can find same can define constraints. how alter query first unused number after that's greater 100

e.g. if have 23, 56, 100, 101, 103 in table should 102.

in mysql , postgresql

select  id + 1    test mo   not exists         (         select  null            test mi            mi.id = mo.id + 1         ) , mo.id> 100 order         id limit 1

fiddle mysql , fiddle postgresql

in ms sql 

select  top 1         id + 1    test mo   not exists         (         select  null            test mi            mi.id = mo.id + 1         )           , mo.id > 100 order         id

fiddle


Comments

Post a Comment

Popular posts from this blog

html5 - What is breaking my page when printing? -

-
Image
i have questioner , don't know why when printing it's creating break before first question. live demo (link) i able resolve issue removing fieldset container had wrapped in.. having fieldset element causing of fields grouped together, , since not fit on first page, being pushed second page. removing fieldset element, able firefox print first 2 questions on page 1 identically chrome. it seems not new problem firefox , fieldset not playing nice found old bugzilla ticket 2008 has persisted , still being commented on in 2014 (link) if retaining fieldset important, found solution else came here (link) <script type='text/javascript'> $(window).bind('beforeprint', function(){ $('fieldset').each( function(item) { $(this).replacewith($('<div class="fieldset">' + this.innerhtml + '</div>')); } ) }); $(window).bind(
Read more

c# - must be a non-abstract type with a public parameterless constructor in redis -

-
when save object, got below error must non-abstract type public parameterless constructor in order use parameter 't' in generic type or method 'servicestack.redis.redisclient.store<t>(t) redisclass.getinstnace().store(msg); // error here redisclass.getinstnace().save(); as third party's class, can not edit how save object? could create wrapper around third party object call constructor, store wrapper? e.g. public class mywrapper { public thirdpartyobject thirdpartyinstance { get; set; } public mywrapper() { thirdpartyinstance = new thirdpartyobject("constructors"); } }
Read more

ajax - PHP/JSON Login script (Twitter style) not setting sessions -

-
i'm having trouble getting twitter style login work properly, reason gets stuck at session_register("useremail"); session_register("userpass"); and doesn't redirect after it. if enter wrong account data, works , appropriate error message pops up. this full code: <?php if(empty($_post['email']) || empty($_post['password'])) { die(msg(0,"all fields required")); } if(!(preg_match("/^[\.a-z0-9_\-\+]+[@][a-z0-9_\-]+([.][a-z0-9_\-]+)+[a-z]{1,4}$/", $_post['email']))) die(msg(0,"you haven't provided valid e-mail")); $host="localhost"; $username="root"; $password="x"; $db_name="x"; $tbl_name="x"; mysql_connect("$host", "$username", "$password")or die("cannot connect"); mysql_select_db("$db_name")or die("cannot select db"); $useremail=$_post['email']; $userpass=
Read more