NAME

DBIx::SQLEngine::Driver::NullP - Extends SQLEngine for Simple Testing

SYNOPSIS

DBI Wrapper: Adds methods to a DBI database handle.

  my $sqldb = DBIx::SQLEngine->new( 'dbi:NullP:' );

Testing Subclass: To allow basic framework testing.

  $sqldb->next_result(
    rowcount => 1,
    hashref => [ { id => 201, name => "Dave Jones" } ],
  );
  
  my $rows = $sqldb->fetch_select( 
    table => 'students' 
  );
  
  ok( $sqldb->last_query, 'select * from students' );
  ok( scalar @$rows == $sqldb->last_result->{rowcount} );

DESCRIPTION

This package provides a subclass of DBIx::SQLEngine which works with the DBI's DBD::NullP to provide a simple testing capability. See the "t/null.t" test script for a usage example.

Queries using the NullP driver and subclass keep track of the SQL statements that are executed against them, allowing a simple way of checking whether the SQL generation code is working as expected. You can also provide raw results to be returned by the next query, in order to confirm that other aspects of the result processing are operational.

TESTING INTERFACE

To simulate normal driver operation, before executing your query, load the results you would expect to receive using next_result, and afterwards confirm that the SQL statement and parameters used matched what you expected.

next_result()

  $sqldb->next_result( 
    rowcount => $number, 
    hashref => $array_of_hashes, 
    arrayref => $array_of_arrays, 
    columns => $array_of_hashes,
  )

Sets up the values that will be returned by the next query.

last_query()

  $sqldb->last_query() : $statement_and_params

Returns the most recent query and parameters captured by prepare_execute(). Parameters are joined by "/" characters.

last_result()

  $sqldb->last_result() : $result_hash_ref

Returns the values set with next_result() and used by the most recent query.

INTERNAL STATEMENT METHODS (DBI STH)

Statement Handle Lifecycle

prepare_execute()

  $sqldb->prepare_execute ($sql, @params) : $sth

Captures the statement and parameters that would otherwise have been sent to the Null driver to be used for later reporting by last_query().

done_with_query()

  $sqldb->done_with_query ($sth) : ()

Clears the values stored by next_result.

Retrieving Rows from a Statement

get_execute_rowcount()

  $sqldb->get_execute_rowcount ($sth) : $row_count

Returns the value stored by next_result() using the key "rowcount".

fetchall_hashref()

  $sqldb->fetchall_hashref ($sth) : $array_of_hashes

Returns the value stored by next_result() using the key "hashref".

fetchall_hashref_columns()

  $sqldb->fetchall_hashref ($sth) : $array_of_hashes
  $sqldb->fetchall_hashref ($sth) : ( $array_of_hashes, $column_info )

Returns the value stored by next_result() using the key "hashref", and if called in a list context, also returns the value for the key "columns".

fetchall_arrayref()

  $sqldb->fetchall_arrayref ($sth) : $array_of_arrays

Returns the value stored by next_result() using the key "arrayref".

fetchall_arrayref_columns()

  $sqldb->fetchall_hashref ($sth) : $array_of_arrays
  $sqldb->fetchall_hashref ($sth) : ( $array_of_arrays, $column_info )

Returns the value stored by next_result() using the key "arrayref", and if called in a list context, also returns the value for the key "columns".

retrieve_columns()

  $sqldb->retrieve_columns ($sth) : $column_info

Retrieves the value stored by next_result() using the key "columns".

visitall_hashref()

  $sqldb->visitall_hashref ($sth, $coderef) : ()

Uses the value stored by next_result() using the key "hashref". Calls the coderef on each row with values as a hashref, and returns a list of their results.

visitall_array()

  $sqldb->visitall_array ($sth, $coderef) : ()

Uses the value stored by next_result() using the key "arrayref". Calls the coderef on each row with values as a list, and returns a list of their results.