(select 1 from(select count(*), concat(( select( select unhex(hex
select number, text from test_table union all select number, text from test_table_2. Здесь уже вывелись все строки, так как мы указали union all. А теперь давайте рассмотрим, какие могут быть ошибки даже в этом простом запросе.
If you had SELECT * FROM users and users had 4 columns, the UNION must also have 4 columns. As a result, they just used `NULL values to populate those columns.
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...
99 or 1=1 union select null, concat(table_name,0x0a,column_name) from information_ schema.columns - since where clause cannot be used
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
+and (select 1)=(Select 0xAAAAAAAAAAAAAAAAAAAAA 1000 more A’s). this AAAAA it's more 1000 A. Example in URL
select, is obvious. null, is just a place holder that is used because a union statement requires that the number of fields match the 1st query that it’s appending to.
If the separator is NULL, the result is NULL. mysql> SELECT CONCAT_WS(',','First name','Second name','Last
String Functions ASCII Char Charindex Concat Concat with + Concat_WS