public static function changeSchema(array &$field, array $column_renames = array())
{
// Update the field schema
$old_schema = array_intersect_key($field, array('columns' => '', 'indexes' => '', 'foreign keys' => ''));
module_load_install($field['module']);
$new_schema = (array) module_invoke($field['module'], 'field_schema', $field);
$new_schema += array('columns' => array(), 'indexes' => array(), 'foreign keys' => array());
$field['data']['columns'] = $new_schema['columns'];
$field['data']['indexes'] = $new_schema['indexes'];
$field['data']['foreign keys'] = $new_schema['foreign keys'];
$data_table = _field_sql_storage_tablename($field);
$revision_table = _field_sql_storage_revision_tablename($field);
// Validate that all the columns described in the existing schema actually exist.
foreach (array_keys($old_schema['columns']) as $old_column) {
$old_column_name = _field_sql_storage_columnname($field['field_name'], $old_column);
if (!db_field_exists($data_table, $old_column_name)) {
throw new Exception();
}
if (!db_field_exists($revision_table, $old_column_name)) {
throw new Exception();
}
// Attempt to re-use any columns that have the same name.
// This can be skipped by setting $column_renames['column-name'] = FALSE;
if (!empty($new_schema['columns'][$old_column]) && !isset($column_renames[$old_column])) {
$column_renames[$old_column] = $old_column;
}
}
// Validate that any columns to be renamed actually exist.
foreach ($column_renames as $old_column => $new_column) {
if (!isset($old_schema['columns'][$old_column])) {
throw new Exception("Cannot rename field {$field['field_name']} column {$old_column} because it does not exist in the old schema.");
}
if (!isset($new_schema['columns'][$new_column])) {
throw new Exception("Cannot rename field {$field['field_name']} column {$old_column} to {$new_column} because it does not exist in the new schema.");
}
}
// Remove all existing indexes.
foreach ($old_schema['indexes'] as $index => $index_fields) {
$index_name = _field_sql_storage_indexname($field['field_name'], $index);
if (db_index_exists($data_table, $index_name)) {
watchdog('helper', "Dropped index {$data_table}.{$index_name}");
db_drop_index($data_table, $index_name);
}
if (db_index_exists($revision_table, $index_name)) {
watchdog('helper', "Dropped index {$revision_table}.{$index_name}");
db_drop_index($revision_table, $index_name);
}
}
// Rename any columns.
foreach ($column_renames as $old_column => $new_column) {
$old_column_name = _field_sql_storage_columnname($field['field_name'], $old_column);
if ($new_column === FALSE) {
db_drop_field($data_table, $old_column_name);
watchdog('helper', "Dropped column {$data_table}.{$old_column_name}");
db_drop_field($revision_table, $old_column_name);
watchdog('helper', "Dropped column {$revision_table}.{$old_column_name}");
unset($old_schema['columns'][$old_column]);
} else {
$new_column_name = _field_sql_storage_columnname($field['field_name'], $new_column);
db_change_field($data_table, $old_column_name, $new_column_name, $new_schema['columns'][$new_column]);
watchdog('helper', "Changed column {$data_table}.{$old_column_name}<br/><pre>" . print_r($new_schema['columns'][$new_column], TRUE) . '</pre>');
db_change_field($revision_table, $old_column_name, $new_column_name, $new_schema['columns'][$new_column]);
watchdog('helper', "Changed column {$revision_table}.{$old_column_name}<br/><pre>" . print_r($new_schema['columns'][$new_column], TRUE) . '</pre>');
// Remove these fields so they aren't removed or added in the code below.
unset($new_schema['columns'][$new_column]);
unset($old_schema['columns'][$old_column]);
}
}
// Remove any old columns.
$old_columns = array_diff_key($old_schema['columns'], $new_schema['columns']);
foreach (array_keys($old_columns) as $old_column) {
$old_column_name = _field_sql_storage_columnname($field['field_name'], $old_column);
db_drop_field($data_table, $old_column_name);
watchdog('helper', "Dropped column {$data_table}.{$old_column_name}");
db_drop_field($revision_table, $old_column_name);
watchdog('helper', "Dropped column {$revision_table}.{$old_column_name}");
}
// Add any new columns.
$new_columns = array_diff_key($new_schema['columns'], $old_schema['columns']);
foreach (array_keys($new_columns) as $new_column) {
$new_column_name = _field_sql_storage_columnname($field['field_name'], $new_column);
db_add_field($data_table, $new_column_name, $new_schema['columns'][$new_column]);
watchdog('helper', "Added column {$data_table}.{$new_column_name}");
db_add_field($revision_table, $new_column_name, $new_schema['columns'][$new_column]);
watchdog('helper', "Added column {$revision_table}.{$new_column_name}");
}
// Re-add indexes.
foreach ($new_schema['indexes'] as $index => $index_fields) {
foreach ($index_fields as &$index_field) {
if (is_array($index_field)) {
$index_field[0] = _field_sql_storage_columnname($field['field_name'], $index_field[0]);
} else {
$index_field = _field_sql_storage_columnname($field['field_name'], $index_field);
}
}
$index_name = _field_sql_storage_indexname($field['field_name'], $index);
db_add_index($data_table, $index_name, $index_fields);
watchdog('helper', "Added index {$data_table}.{$index_name}<br/><pre>" . print_r($index_fields, TRUE) . '</pre>');
db_add_index($revision_table, $index_name, $index_fields);
watchdog('helper', "Added index {$revision_table}.{$index_name}<br/><pre>" . print_r($index_fields, TRUE) . '</pre>');
}
}
/**
* Asserts that a given field can be added and removed from a table.
*
* The addition test covers both defining a field of a given specification
* when initially creating at table and extending an existing table.
*
* @param $field_spec
* The schema specification of the field.
*/
protected function assertFieldAdditionRemoval($field_spec)
{
// Try creating the field on a new table.
$table_name = 'test_table_' . $this->counter++;
$table_spec = array('fields' => array('serial_column' => array('type' => 'serial', 'unsigned' => TRUE, 'not null' => TRUE), 'test_field' => $field_spec), 'primary key' => array('serial_column'));
db_create_table($table_name, $table_spec);
$this->pass(format_string('Table %table created.', array('%table' => $table_name)));
// Check the characteristics of the field.
$this->assertFieldCharacteristics($table_name, 'test_field', $field_spec);
// Clean-up.
db_drop_table($table_name);
// Try adding a field to an existing table.
$table_name = 'test_table_' . $this->counter++;
$table_spec = array('fields' => array('serial_column' => array('type' => 'serial', 'unsigned' => TRUE, 'not null' => TRUE)), 'primary key' => array('serial_column'));
db_create_table($table_name, $table_spec);
$this->pass(format_string('Table %table created.', array('%table' => $table_name)));
// Insert some rows to the table to test the handling of initial values.
for ($i = 0; $i < 3; $i++) {
db_insert($table_name)->useDefaults(array('serial_column'))->execute();
}
db_add_field($table_name, 'test_field', $field_spec);
$this->pass(format_string('Column %column created.', array('%column' => 'test_field')));
// Check the characteristics of the field.
$this->assertFieldCharacteristics($table_name, 'test_field', $field_spec);
// Clean-up.
db_drop_field($table_name, 'test_field');
// Add back the field and then try to delete a field which is also a primary
// key.
db_add_field($table_name, 'test_field', $field_spec);
db_drop_field($table_name, 'serial_column');
db_drop_table($table_name);
}
/**
* Asserts that a newly added field has the correct characteristics.
*/
protected function assertFieldCharacteristics($table_name, $field_name, $field_spec)
{
// Check that the initial value has been registered.
if (isset($field_spec['initial'])) {
// There should be no row with a value different then $field_spec['initial'].
$count = db_select($table_name)->fields($table_name, array('serial_column'))->condition($field_name, $field_spec['initial'], '<>')->countQuery()->execute()->fetchField();
$this->assertEqual($count, 0, 'Initial values filled out.');
}
// Check that the default value has been registered.
if (isset($field_spec['default'])) {
// Try inserting a row, and check the resulting value of the new column.
$id = db_insert($table_name)->useDefaults(array('serial_column'))->execute();
$field_value = db_select($table_name)->fields($table_name, array($field_name))->condition('serial_column', $id)->execute()->fetchField();
$this->assertEqual($field_value, $field_spec['default'], 'Default value registered.');
}
db_drop_field($table_name, $field_name);
}
