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MySQL CONCAT returns NULL if any field contain NULL

stackoverflow.com

I have following data in my table "devices" … I executed below query … It returns result given below … How to come out of this so that it should ignore NULL AND result should be …

SQL using If Not Null on a Concatenation - Stack Overflow

stackoverflow.com

If I have the table … This will display Firstname-Middlename-Surname e.g. … The second one (Jane’s) displays correct, however since John doesn’t have a middlename, I want it to ignore the second dash.

sql - CONCAT'ing NULL fields - Stack Overflow

stackoverflow.com

I have a table with three fields, FirstName, LastName and Email. Here's some dummy data: … Now, if I do: … Vitals for Joe is null, as there is a single null field. How do you overcome this behaviour?

Concat Values In MySQL Query(To Handle Null Values)

stackoverflow.com

I am writing a PHP and MySQL application in which i have to concatenate multiple column values into one single column.I would have used the concat() function,but it does not handle null values...

group concat - MySQL GROUP_CONCAT with Nulls - Stack Overflow

stackoverflow.com

Is there an option to make MySQL's Group_Concat function include nulls? Consider the following example from my source table: … When I query on the selection table with GROUP_CONCAT...

Confusing SQL error in SELECT NULL, *, NULL, NULL - Stack Overflow

stackoverflow.com

The Background I was trying to solve the fourth realistic mission in hackthissite.org, and couldn't figure out exactly what SQL I should inject into the URL to retrieve the list of emails.

sql injection "union select null" - CodeProject

www.codeproject.com

Union select null, null, null, null, null, null, null from information_schema.tables. for a small database containing three tables. this instruction is used in sql injection I tried it and it worked but I didn't really know how it works can somebody help me...

SQL NULL Values - IS NULL and IS NOT NULL

www.w3schools.com

A field with a NULL value is one that has been left blank during record creation! How to Test for NULL Values?

Заметка про NULL / Хабр

habr.com

Даже выражение NULL != NULL не будет истинным, ведь нельзя однозначно сравнить одну неизвестность с другой. Кстати, ложным это выражение тоже не будет, потому что при вычислении условий Oracle не ограничивается состояниями ИСТИНА и ЛОЖЬ.

SET CONCAT_NULL_YIELDS_NULL in SQL Server

www.tech-recipes.com

CONCAT_NULL_YIELDS_NULL control whether concatenation results shall be treated as NULL or empty string values.

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