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...
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/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?
null - Почему UNION возвращает только один null?
Вывод имён колонок (MySQL >= 4.1 колонки NOT NULL).
When doing SELECT … UNION SELECT, where do you put the the INTO OUTFILE clause? On the first SELECT, on the last or somewhere else? The manual has the answer here, to quote
INSERT INTO tablesB VALUES (2),(2),(NULL) GO. CREATE CLUSTERED INDEX Ix_ID ON tablesB(Id) --. Now go through some of the queries
SELECT * FROM ( SELECT 1 AS a FROM DUAL UNION ALL SELECT 2 AS a FROM DUAL UNION ALL SELECT 3 AS a FROM DUAL ) t. Now that you’re seeing that VALUES() and derived tables are really the same thing, conceptually, let’s review the INSERT statement, which comes in two flavors
SELECT 2 AS value UNION ALL SELECT NULL ). SELECT l.* FROM t_left l WHERE NOT EXISTS (.