Question

i have mysql code for input data:

 $sql = "INSERT IGNORE INTO inspection_report ";
  $sql.= "(Model,       Serial_number,       Line,        Shift,     Inspection_datetime,         Range_sampling,       Packing, ";
  $sql.= "Accesories,       Appearance,      Tuner,        General_operation,       Class,      Status,         Remark, ";
  $sql.= "NIK) ";
  $sql.= "VALUES ('";
  $sql.= $Model."','".$Serial_number."', '".$Line."','".$Shift."','".postVar('insp_date')." ".postVar('time')."','".$Range_sampling."','".$Packing."','";
  $sql.= $Accesories."','".$Appearance."','".$Tuner."','".$General_operation."','".$Class."','".$Status."','".$Remark."','";
  $sql.= $NIK."')";

i want to use IGNORE.but how to prevent duplicate only at Model,Serial_number,Line?

Answer 1

From the documentation

INSERT

If you use the IGNORE keyword, errors
that occur while executing the INSERT
statement are treated as warnings
instead. For example, without
IGNORE, a row that duplicates an
existing UNIQUE index or PRIMARY KEY
value in the table causes a
duplicate-key error and the statement
is aborted. With IGNORE, the row still
is not inserted, but no error is
issued.

So that tells me that either Model,Serial_number,Line must be the Primary key, or you need to create an Unique index on these columns.