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add column to mysql table if it does not exist
...uld be to just try the ALTER TABLE ADD COLUMN command. It should throw an error if the column already exists.
ERROR 1060 (42S21): Duplicate column name 'newcolumnname'
Catch the error and disregard it in your upgrade script.
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What is the difference between syntax and semantics in programming languages?
...ement has no meaning (according to the C language rules) and thus it is an error even though the statement is syntactically correct.
If x is a pointer to some data type, the meaning of the statement is to "add sizeof(some data type) to the value at address x and store the result into the location at...
Composer Warning: openssl extension is missing. How to enable in WAMP
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what should i do for xampp?.. I got the error like this Message could not be sent. Mailer Error: Extension missing: openssl ,,,
– pcs
May 29 '15 at 12:38
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jQuery .live() vs .on() method for adding a click event after loading dynamic html
I am using jQuery v.1.7.1 where the .live() method is apparently deprecated.
7 Answers
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Function to convert column number to letter?
...n - checking first if the number is positive, since otherwise you run into errors. if lngcol <=0 then
– Selkie
Nov 29 '17 at 20:52
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Escape @ character in razor view engine
...e.g. @RenderBody() . If I write @test on my cshtml page it gives me parse error
15 Answers
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Simplest way to read json from a URL in java
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Why i am getting this error "The constructor JSONObject(String) is undefined" in the line of JSONObject json = new JSONObject(jsonText); in "readJsonFromUrl" method..? @RolandIllig
– Karthick pop
Nov 5 '14 at...
Generic method multiple (OR) type constraint
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What I'm doing, in fact, is writing a simple error logging function. I'd like that last parameter to either be a string of info about the error, or an exception, in which case I save e.message + e.stacktrace as a string anyway.
– Mansfield
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What is a web service endpoint?
Let's say my web service is located at http://localhost:8080/foo/mywebservice and my WSDL is at http://localhost:8080/foo/mywebservice?wsdl .
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What happens if a finally block throws an exception?
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@HenkHolterman: Disk-full errors aren't very common on a directly-connected primary hard disk, but programs sometimes write files to removable or networked disks; problems can be much more common with those. If someone yanks out a USB stick before a ...