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Node.js MySQL Delete

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Delete Record

You can delete records from an existing table by using the "DELETE FROM" statement:

Example

Delete any record with the address "Mountain 21":
var mysql = require('mysql');

var con = mysql.createConnection({
  host: "localhost",
  user: "yourusername",
  password: "yourpassword",
  database: "mydb"
});

con.connect(function(err) {
  if (err) throw err;
  var sql = "DELETE FROM customers WHERE address = 'Mountain 21'";  con.query(sql, function (err, result) {
    if (err) throw err;
    console.log("Number of records deleted: " + result.affectedRows);
  });
});
Run example »
Notice the WHERE clause in the DELETE syntax: The WHERE clause specifies which record or records that should be deleted. If you omit the WHERE clause, all records will be deleted!
Save the code above in a file called "demo_db_delete.js" and run the file:
Run "demo_db_delete.js"
C:\Users\Your Name>node demo_db_delete.js
Which will give you this result:
Number of records deleted: 1

The Result Object

When executing a query, a result object is returned.
The result object contains information about how the query affected the table.
The result object returned from the example above looks like this:
{
  fieldCount: 0,
  affectedRows: 1,
  insertId: 0,
  serverStatus: 34,
  warningCount: 0,
  message: '',
  protocol41: true,
  changedRows: 0
}
The values of the properties can be displayed like this:

Example

Return the number of affected rows:
console.log(result.affectedRows)
Which will produce this result:
1

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