ADODB Getting the column count

Question

Hi, I was reading through our code base at my company and I saw something that seemed like it could be done better.

$dbRow = $dbh->Execute("SELECT * FROM database.table LIMIT 1");
$tableColumnCount = $dbRow->_numOfFields;

Is this the only way to get a column count using ADODB? It just seems silly to have to execute a query so you can ask the question.

Answer 1

Whichever way, you'll have to end up hitting the database unless your program can magically know the schema of the table. If LIMIT 0 is legal in MySQL then this would be slightly more efficient - as I expect would replacing LIMIT 1 with WHERE 1 = 0.

Answer 2

You can use the INFORMATION_SCHEMA.COLUMNS table:

SELECT COUNT(*) 
  FROM INFORMATION_SCHEMA.COLUMNS
 WHERE table_name = 'your_table_name'
   AND table_schema = 'your_database_name'

That said, you might want to run the FLUSH TABLES command prior to for the INFORMATION_SCHEMA.COLUMNS to reflect existing tables and columns because the data is cached.

Answer 3

MetaColumns or MetaColumnNames should give you this information