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 …
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.
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.
Postgres is the database Can I use a NULL value for a IN clause? example: … I want to limit to these four values. I have tried the above statement and it doesn't work...
What is the difference between … and … and why does the latter not work?
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...
Note: A NULL value is different from a zero value or a field that contains spaces. A field with a NULL value is one that has been left blank during record creation!
NULL может означать следующее: - NULL (Си и Си++) — в языках программирования Си и C++ означает нулевой указатель; аналог для ссылок в Java — null (указателей в Java нет вообще) . - NULL (SQL) — специальное значение (псевдозначение) , которое может быть записано в поле...
A null allele is a nonfunctional copy of a gene caused by a genetic mutation. This mutation can cause complete lack of production of the associated gene product or a product that does not function properly. A null allele cannot be distinguished from deletion of the entire locus solely from phenotypic...