CODEWITHSUNDEEP
phpmysql
dsuma
dsuma

Reputation: 1010

How Can I prevent Duplicates in my database

I have a CSV File that I am throwing into a DB. It does this correctly but I dont want repeating records obviously. Any Ideas how I can record only unique ones? I don't want to throw them into the DB then run a DELETE query because well thats not time effective.

if (($handle = fopen($csvfile, "r")) !== FALSE) {
            while (($data = fgetcsv($handle,1000, ',')) !== FALSE) {
                $count ++;
                if ($count > 1) {
                    mysqli_query($con, "INSERT INTO $table2 (id, cat) VALUES ('".$data[0]."', '".$data[1]."')");  
                    mysqli_query($con, "INSERT INTO $table1 (id, cat) VALUES ('".$data[2]."', '".$data[3]."')"); 
                    mysqli_query($con, "INSERT INTO $table3 (id, word) VALUES ('".$data[4]."', '".$data[5]."')"); 
                    mysqli_query($con, "INSERT INTO $table4 (id, cl, co, imp) VALUES ('".$data[0]."','".$data[6]."', '".$data[7]."', '".$data[8]."')"); 
                }
            }

        }

Upvotes: 0

Views: 106

Answers (2)

pratim_b
pratim_b

Reputation: 1210

you can either use teh unique key way or you can use 

WHERE NOT EXISTS

on a specific column which you are considering to find the duplicate. So it will be like 

Insert into table name() values () where not exists (Select statement)

Upvotes: 0

웃웃웃웃웃
웃웃웃웃웃

Reputation: 11984

One way is after inserting all the records you can add a unique index and drop the duplicates with

ALTER IGNORE TABLE your_table
ADD UNIQUE INDEX dup_idx (column_1, column_2, column_3, column_3);

Another way is that add this unique index before insertion then use insert ignore query 

INSERT IGNORE INTO table (column1,column2) VALUES ('value1','value2');

This will ignore the error occuring on insertion of duplicate entries since unique index is there also it will skip the duplicate entry insertion.

Upvotes: 3

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