Hi all,
I've run into a bit of a problem with bind params using the DBI. In short, the problem is: how do i get a DB defined default value into a column, using an insert query that is expecting a bound value for that column?

Here is a much more detailed explanation of what im trying to accomplish. Lets say i have a table defined by: 
CREATE TABLE blah (
   A INT,
   B INT NOT NULL DEFAULT 0
)

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And i create a query to write to this table, such as: 
   my $query = "INSERT INTO blah SET A = ?, B = ? ";
   my $query_handle = $db_handle->prepare($query);

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Then i have an array of hashrefs, each containing 1 row of values to insert, such as 
   my @to_insert = (
      { 'A' => 1, 'B' => 1 },
      { 'B' => 2 },
      { 'A' => 3 },
   );

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Now i have a loop to go through and insert all of these rows. When i wasnt using bind params, if a column doesnt have a value, i just dont mention it in the query, and the DB takes care of inserting a default value. But when using bind params, i cant figure out a way to get the DB to insert the default value, without creating a separate query for each combination of fields to insert.

For this trivial example, there are only 3 queries, but in general, if there are n columns, there are (2^n - 1) possible column combinations, and i dont want to have to create each one.

I dont even know if this is possible, but any insight would be great.

In reply to DBI bind params & column defaults by shemp

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