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 …
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?
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.
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...
select a,b,null,null from table1 union select null,null,c,d from table2 union select null,null,null,null,e,f from table3.
I dont want to return null value, how to check not null or how to make isset cond in query …
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...
mysql> SELECT CONCAT_WS(',','First name','Second name','Last Name')
Если параметр SET CONCAT_NULL_YIELDS_NULL установлен в OFF, любое применение инструкций CREATE, UPDATE, INSERT и DELETE к таблицам с индексами на вычисляемых столбцах или к индексированным представлениям завершится...
A field with a NULL value is a field with no value. If a field in a table is optional, it is possible to insert a new record or update a record without adding a value to this