Top "Exists" questions

How to check the existence of a namespace in php

I have a php library https://github.com/tedivm/Fetch and it uses Fetch namespace and I would like to …

php class namespaces exists

Exists / not exists: 'select 1' vs 'select field'

Which one of the two would perform better(I was recently accused of not being careful with my code because …

sql sql-server oracle exists

How can you check to see if a file exists (on the remote server) in Capistrano?

Like many others I've seen in the Googleverse, I fell victim to the File.exists? trap, which of course checks …

ruby file capistrano exists

How to check existence of an input argument for R functions

I have a function defined as myFun <- function(x, y, ...) { # using exists if (exists("z")) { print("exists z!") } # …

r function arguments exists

JQuery: Check if element exists alongside '.remove()'

I know you can check if an element exists with $('div').length, but when an element is destroyed using .remove(), .…

jquery exists

Check if twitter username exists

Is there a way to check if a twitter username exists? Without being authenticated with OAuth or the twitter basic …

authentication twitter oauth exists

Correct PHP way to check if external image exists?

I know that there are at least 10 the same questions with answers but none of them seems to work for …

php image exists

How to check if a DataBase exist or not after the connection is made JAVA

I have a big question... I have a database java program creation. I want to know if the database exists …

java database exists database-engine

How to check if a row exists in a PostgreSQL stored procedure?

I writing a stored procedure in postgres where I need to check if a row exists then act accordingly. something …

postgresql stored-procedures plpgsql exists

How do I check for the existence of an external file with XSL?

I've found a lot of examples that reference Java and C for this, but how do I, or can I, …

xslt document external xsl-fo exists