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.
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
union all select null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null
...other is null, in this case, you'll take the non-null value. a situation where both column will be non-null but are not the same. otherwise, which one would you
So as you see there are really different types of ranges in MySQL.
The null character (also null terminator or null byte) is a control character with the value zero. It is present in many character sets, including ISO/IEC 646 (or ASCII), the C0 control code, the Universal Coded Character Set (or Unicode), and EBCDIC.
-999.9+union+all+select+%27R3DM0V3_hvj_injection',null%2CNULL%2CNULL%2CNULL%2CNULL%2CNULL%2CNULL
SELECT CAST(NULL AS float) AS v UNION SELECT CAST('1.0' AS float) AS v. A column with type int doesn't have these problems.