aLl sElEcT null null null null.
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...
SELECT * FROM nullTest WHERE name=null; Bad Request: Unsupported null value for indexed column name. And again, this is done under the premise that
Ref: 999999.9' union all select 99,2 and '0'='0.
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 field.
select cast (2000 as type of quint) from rdb$database select cast (2000 as int) from rdb$database. If TYPE OF is used with a (VAR)CHAR type, its character.
SELECT CHAR(0x66) (S) SELECT 0x5045 (this is not an integer it will be a string from Hex) (M) SELECT 0x50
R language supports several null-able values and it is relatively important to understand how these values behave, when making data pre-processing and data