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...
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.
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2.1 Команда UNION Cамое полезное, в нашем случае, это команда UNION (кто не знает лезть
Yin Yang Composition Icon Of Zero And Null Digits In Various Sizes Vector Digits Are Scattered Into.
11223344) UNION SELECT NULL,NULL,NULL,NULL WHERE 1=2 –- Если нет ошибки, значит синтаксис верный, т.е. используется MS SQL Server.
Union select null, null, null, null, null, null, null from information_schema.tables. for a small database containing three tables.
/index.php?id=null union all select 1,2,3,4,user(),6,database(),8,version(),10,11,12,1 3,14,15–. As you can see we selected values from the showing columns, what if we want to clean this up a bit, and put all of those selected values in one column? This is where concat() comes in
Union [all]. Select. column3, column4. FROM. table2; To use the UNION operator, you write the dividual SELECT statements and join them by the keyword UNION.
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