Benchmark(count,expr) ,这个函数执行的结果,是将表达式 expr 执行count 次。因此,利用benchmark函数,可以让同一个函数执行若干次,使得结果返回的时间比平时要长,通过时间长短的变化,可以判断注入语句是否执行成功。这是一种边信道攻击,这个技巧在盲注中被称为Timing Attack,也就是时间盲注。
start,length):对于给定字符串string,从start位开始截取,截取length长度 ,如 substr("chinese",3,2)="in" substr()、stbstring()、mid() :三个函数的用法、功能均一致 concat(username):将查询到的username连在一起,默认用逗号分隔 concat(str1,'*',str2):将字符串str1和str2的数据查询到一起,...
SQL_MAX_TABLES_IN_SELECT SQL_MAX_USER_NAME_LEN 标量函数信息 InfoType 参数的以下值返回有关数据源和驱动程序支持的标量函数的信息。 有关标量函数的详细信息,请参阅 附录E:标量函数。 SQL_CONVERT_FUNCTIONS SQL_NUMERIC_FUNCTIONS SQL_STRING_FUNCTIONS SQL_SYSTEM_FUNCTIONS SQL_TIMEDATE_ADD_INTERVALS SQL_TIME...
length(str) : 返回给定字符串的长度,如 length("string")=6 substr(string,start,length):对于给定字符串string,从start位开始截取,截取length长度 ,如 substr("chinese",3,2)="in" substr()、stbstring()、mid() :三个函数的用法、功能均一致 concat(username):将查询到的username连在一起,默认用逗号分隔...
Array data type in SQL server Array's IN SQL SERVER? ASCII values for extended characters Assign empty string '' if datetime is null Assign EXEC output to Variable Assigning NULL value to column name using Case Statement of where is SQL SERVER 2008 atomic if not exists() and insert or upd...
Column names must comply with the rules for identifiers and must be unique in the table. column_name can consist of 1 through 128 characters. data_type Specifies the column data type. For Transact-SQL functions, all data types, including CLR user-defined types, are allowed except timestamp....
Column names must comply with the rules for identifiers and must be unique in the table. column_name can consist of 1 through 128 characters. data_type Specifies the column data type. For Transact-SQL functions, all data types, including CLR user-defined types, are allowed except timestamp....
NOT LIKE "ABCD"%Used anywhere in a string to match a sequence of zero or more characters (...
trim([characters from] string):去掉字符串头尾指定的空格或字符。 regexp_extract(string, pattern, index):指定模式,并返回特定位置(从1开始计算)的匹配结果。 regexp_replace(string, pattern, replacement):将字符串中的符合模式的字符串替换成替换字符串。
from (select count(a.字段) as rscount, TO_CHAR(CREATEDATE, 'yyyy-mm') timevalue, substr(('xx'||a.shiguid),1,8) as 字段 from 表 a where 字段 in (select trim(字段) from 表 where 字段 like 'xxx%') group by 字段,TO_CHAR(CREATEDATE, 'yyyy-mm')) t1, ...