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.
999999.9' union all select 999,2 and '0'='0 где купить в аптеках, Поиск и заказ лекарств в аптеках Санкт-Петербурга и Ленинградской области онлайн, бронирование и доставка лекарств.
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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Существуют специальные операторы IS NULL и IS NOT NULL, которые позволяют производить сравнения с NULLами.
The IS NULL operator is used to test for empty values (NULL values). The following SQL lists all customers with a NULL value in the "Address" field: Example. SELECT CustomerName, ContactName, Address FROM Customers WHERE Address IS NULL
I realize this may be marked as duplicate, but I'm specifically asking in relation to SQL Server 2005 I have read conflicting advice on the internet so I'm asking here.
The Oracle IS NOT NULL condition is used to test for a NOT NULL value.
Null (or NULL) is a special marker used in Structured Query Language to indicate that a data value does not exist in the database. Introduced by the creator of the relational database model, E. F. Codd...