In an attempt to dump a MySQL database, an issue arises where the file is created but remains empty. This article examines potential reasons for this behavior and provides solutions based on the given code snippet.
The initial problem stemmed from a failure to connect to the database before issuing queries. Additionally, the connection.destroy() method was being called prematurely, resulting in the interruption of pending SQL calls.
To rectify these issues, the following modifications were made:
<code class="javascript">var mysql_backup = function(){ //... this.connection.connect(function (err, empty) { //... }); //... this.get_tables = function(callback){ var counter = 0; var me = this; this.query('SHOW TABLES', function(tables) { for (table in tables){ counter++; me.query( 'SHOW CREATE TABLE ' + tables[table].Tables_in_mvc, function(r){ //... counter--; if (counter === 0){ me.save_backup(); me.connection.destroy(); } } ) } }); }; //... }; var db = new mysql_backup; db.init(); db.get_tables();</code>
To enhance the code's readability and effectiveness, further improvements could include:
By correcting the connection issue, arranging the callback execution order appropriately, and tracking outstanding SQL calls, the file-emptying problem can be resolved, allowing successful "dumping" of the MySQL database.
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