/**
* Checks whether a given column diff is a logically unchanged binary type column.
*
* Used to determine whether a column alteration for a binary type column can be skipped.
* Doctrine's {@link \Doctrine\DBAL\Types\BinaryType} and {@link \Doctrine\DBAL\Types\BlobType}
* are mapped to the same database column type on this platform as this platform
* does not have a native VARBINARY/BINARY column type. Therefore the {@link \Doctrine\DBAL\Schema\Comparator}
* might detect differences for binary type columns which do not have to be propagated
* to database as there actually is no difference at database level.
*
* @param ColumnDiff $columnDiff The column diff to check against.
*
* @return boolean True if the given column diff is an unchanged binary type column, false otherwise.
*/
private function isUnchangedBinaryColumn(ColumnDiff $columnDiff)
{
$columnType = $columnDiff->column->getType();
if (!$columnType instanceof BinaryType && !$columnType instanceof BlobType) {
return false;
}
$fromColumn = $columnDiff->fromColumn instanceof Column ? $columnDiff->fromColumn : null;
if ($fromColumn) {
$fromColumnType = $fromColumn->getType();
if (!$fromColumnType instanceof BinaryType && !$fromColumnType instanceof BlobType) {
return false;
}
return count(array_diff($columnDiff->changedProperties, array('type', 'length', 'fixed'))) === 0;
}
if ($columnDiff->hasChanged('type')) {
return false;
}
return count(array_diff($columnDiff->changedProperties, array('length', 'fixed'))) === 0;
}
/**
* Returns the SQL clause for altering a column in a table alteration.
*
* This method returns null in case that only the column comment has changed.
* Changes in column comments have to be handled differently.
*
* @param ColumnDiff $columnDiff The diff of the column to alter.
*
* @return string|null
*/
protected function getAlterTableChangeColumnClause(ColumnDiff $columnDiff)
{
$column = $columnDiff->column;
// Do not return alter clause if only comment has changed.
if (!($columnDiff->hasChanged('comment') && count($columnDiff->changedProperties) === 1)) {
$columnAlterationClause = 'ALTER ' . $this->getColumnDeclarationSQL($column->getQuotedName($this), $column->toArray());
if ($columnDiff->hasChanged('default') && null === $column->getDefault()) {
$columnAlterationClause .= ', ALTER ' . $column->getQuotedName($this) . ' DROP DEFAULT';
}
return $columnAlterationClause;
}
}
/**
* Checks whether a column alteration requires dropping its default constraint first.
*
* Different to other database vendors SQL Server implements column default values
* as constraints and therefore changes in a column's default value as well as changes
* in a column's type require dropping the default constraint first before being to
* alter the particular column to the new definition.
*
* @param ColumnDiff $columnDiff The column diff to evaluate.
*
* @return boolean True if the column alteration requires dropping its default constraint first, false otherwise.
*/
private function alterColumnRequiresDropDefaultConstraint(ColumnDiff $columnDiff)
{
// We can only decide whether to drop an existing default constraint
// if we know the original default value.
if (!$columnDiff->fromColumn instanceof Column) {
return false;
}
// We only need to drop an existing default constraint if we know the
// column was defined with a default value before.
if ($columnDiff->fromColumn->getDefault() === null) {
return false;
}
// We need to drop an existing default constraint if the column was
// defined with a default value before and it has changed.
if ($columnDiff->hasChanged('default')) {
return true;
}
// We need to drop an existing default constraint if the column was
// defined with a default value before and the native column type has changed.
if ($columnDiff->hasChanged('type') || $columnDiff->hasChanged('fixed')) {
return true;
}
return false;
}
/**
* Returns the ALTER COLUMN SQL clauses for altering a column described by the given column diff.
*
* @param ColumnDiff $columnDiff The column diff to evaluate.
*
* @return array
*/
private function getAlterColumnClausesSQL(ColumnDiff $columnDiff)
{
$column = $columnDiff->column->toArray();
$alterClause = 'ALTER COLUMN ' . $columnDiff->column->getQuotedName($this);
if ($column['columnDefinition']) {
return array($alterClause . ' ' . $column['columnDefinition']);
}
$clauses = array();
if ($columnDiff->hasChanged('type') || $columnDiff->hasChanged('length') || $columnDiff->hasChanged('precision') || $columnDiff->hasChanged('scale') || $columnDiff->hasChanged('fixed')) {
$clauses[] = $alterClause . ' SET DATA TYPE ' . $column['type']->getSQLDeclaration($column, $this);
}
if ($columnDiff->hasChanged('notnull')) {
$clauses[] = $column['notnull'] ? $alterClause . ' SET NOT NULL' : $alterClause . ' DROP NOT NULL';
}
if ($columnDiff->hasChanged('default')) {
if (isset($column['default'])) {
$defaultClause = $this->getDefaultValueDeclarationSQL($column);
if ($defaultClause) {
$clauses[] = $alterClause . ' SET' . $defaultClause;
}
} else {
$clauses[] = $alterClause . ' DROP DEFAULT';
}
}
return $clauses;
}
/**
* Do checks for column diffs.
*
* @param ColumnDiff $columnDiff
* @param IgnoredChange $ignoredChange
*
* @return boolean
*/
protected function checkColumnDiff(ColumnDiff $columnDiff, IgnoredChange $ignoredChange)
{
if (count($columnDiff->changedProperties) !== 1 && !$columnDiff->hasChanged($ignoredChange->getPropertyName())) {
return false;
}
$propertyName = $columnDiff->changedProperties[0];
$before = $columnDiff->fromColumn->getType()->getName();
$after = $columnDiff->column->getType()->getName();
if ($ignoredChange->matches('changedColumns', $propertyName, $before, $after)) {
return true;
}
return false;
}
/**
* Do checks for column diffs.
*
* @param ColumnDiff $columnDiff
* @param array $alterData
*
* @return boolean
*/
protected function checkColumnDiff(ColumnDiff $columnDiff, array $alterData)
{
if (count($columnDiff->changedProperties) !== 1 && !$columnDiff->hasChanged($alterData['propertyName'])) {
return false;
}
foreach ($alterData['ignoredChanges'] as $keys) {
if ($keys['before'] === $columnDiff->fromColumn->getType()->getName() && $keys['after'] === $columnDiff->column->getType()->getName()) {
return true;
}
}
return false;
}
/**
* Returns the SQL clause for altering a column in a table alteration.
*
* This method returns null in case that only the column comment has changed.
* Changes in column comments have to be handled differently.
*
* @param ColumnDiff $columnDiff The diff of the column to alter.
*
* @return string|null
*/
protected function getAlterTableChangeColumnClause(ColumnDiff $columnDiff)
{
$column = $columnDiff->column;
// Do not return alter clause if only comment has changed.
if (!($columnDiff->hasChanged('comment') && count($columnDiff->changedProperties) === 1)) {
return 'ALTER ' . $this->getColumnDeclarationSQL($column->getQuotedName($this), $column->toArray());
}
}
