PayloadsAllTheThings/MySQL Injection.md at master...
1' UNION SELECT @--+ #The used SELECT statements have a different number of columns 1' UNION SELECT
sql injection "union select null" - CodeProject | To display as
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...
999999.9" //union//all //select //**/union/**/all/**/select/**/concat..."
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...
TSQL - CONCAT_NULL_YIELDS_NULL ON Not Returning Null?
CONCAT_NULL_YIELDS_NULL ON INSERT INTO Mytable(StringValue) SELECT COALESCE
Confusing SQL error in SELECT NULL, *, NULL, NULL - Stack Overflow
UNION ALL SELECT NULL, *, NULL, NULL FROM email. I understand what this does and why; the hacker needs to create a query that has the same number of columns as the query it's being merged with, and shifted around the * to make sure the emails are displayed. That's not my question.
net - Does null == null? - Stack Overflow
null is nothing but internal Pointer with value zero. So it is comparing two references having value zero. In fact object.ReferenceEquals(null, null) is always true because of this fact so you do not need the second check.
SQL NULL Values - IS NULL and IS NOT NULL
Note: A NULL value is different from a zero value or a field that contains spaces.
JavaScript: загадочное дело выражения null >= 0 / Блог... / Хабр
Связано ли это с типом null и с тем, как он обрабатывается, или с тем, как выполняются операции сравнения значений? В итоге я решил докопаться до сути происходящего и начал рыться в единственном источнике истины для JavaScript — в спецификации ECMA.
LEFT JOIN / IS NULL vs. NOT IN vs. NOT EXISTS: nullable columns
When inner.value is marked as NOT NULL, all these queries are semantically equivalent and with proper indexing have similarly optimized execution plans in MySQL. Now, what if inner.value is not nullable and does contain some NULL values? Let's create some sample tables: Table creation details.
NULL (SQL) — Википедия
NULL в Системах управления базами данных (СУБД) — специальное значение (псевдозначение), которое может быть записано в поле таблицы базы данных (БД). NULL соответствует понятию «пустое поле», то есть «поле, не содержащее никакого значения».