public function compile(Database $db)
{
// Start with the basic syntax.
$sql = 'CREATE TABLE ' . $db->quote_table($this->_table['name']);
// You are allowed to create a table without any columns. Dont ask me why.
if (count($this->_table['columns']) > 0) {
// Get ready for the column data.
$sql .= ' (';
// Compile the columns in the normal way.
foreach ($this->_table['columns'] as $name => $data) {
$sql .= Database_Query_Builder::compile_column($data, $db) . ',';
}
// Compile constraints in a normal way
foreach ($this->_table['constraints'] as $name => $data) {
$sql .= Database_Query_Builder::compile_constraint($data, $db) . ',';
}
// Seperate the columns with commars, and add the table constraints at the end.
$sql = rtrim($sql, ',') . ') ';
}
// Process table options
foreach ($this->_table['options'] as $key => $option) {
$sql .= Database_Query_Builder::compile_statement(array($key => $option)) . ' ';
}
// Remove the trailing space.
return rtrim($sql, ' ') . ';';
}
/**
* Compile the SQL query and return it.
*
* @param Database Database instance.
* @return string The SQL query.
*/
public function compile(Database $db)
{
// Initiate the alter statement
$sql = 'ALTER TABLE ' . $db->quote_table($this->_original_name) . ' ';
// If we have a name set, rename the table.
if (isset($this->_new_name)) {
// Prepare the rename SQL
$sql .= 'RENAME TO ' . $db->quote_table($this->_new_name) . '; ';
// Update the new name
$this->_original_name = $this->_new_name;
} elseif (!empty($this->_add_columns) or !empty($this->_add_constraints)) {
// If we have more then one constraint or column, we need brackets
$multi = count($this->_modify_columns) + count($this->_add_constraints) > 1;
// Add the brackets and begin the statement
$sql .= 'ADD ' . ($multi ? '(' : '');
// Loop through each column, compiling it where necessary
foreach ($this->_add_columns as $column) {
$sql .= Database_Query_Builder::compile_column($column, $db) . ',';
}
// Loop through each constraint, compiling it where necessary
foreach ($this->_add_constraints as $constraint) {
$sql .= Database_Query_Builder::compile_constraint($column, $db) . ',';
}
// Remove the trailing commar and append a closing bracket where necessary
$sql = rtrim($sql, ',') . ($multi ? ')' : '') . ';';
} elseif (!empty($this->_modify_columns)) {
// Check to see if we have more then one column
$multi = count($this->_modify_columns) > 1;
// Begin the modify statement, if we have multiple columns, add them as methods.
$sql .= 'MODIFY ' . ($multi ? '(' : '');
// Loop through each column, compile it, then add it to the sql string.
foreach ($this->_modify_columns as $column) {
$sql .= Database_Query_Builder::compile_column($column, $db) . ',';
}
// Return the sql statement with any closing brackets where necessary
$sql = rtrim($sql, ',') . ($multi ? ')' : '') . ';';
} elseif (!empty($this->_drop_columns) or !empty($this->_drop_constraints)) {
// Reset the sql string, multiple drop methods cannot be put in the same query.
$sql = '';
// Foreach drop column, get the SQL and create a statement for it.
foreach ($this->_drop_columns as $column) {
// Start each drop statement as a new query
$sql .= 'ALTER TABLE ' . $db->quote_table($this->_original_name) . ' ' . DB::drop('column', $column)->compile($db) . ';';
}
// Foreach drop constraint
foreach ($this->_drop_constraints as $constraint => $type) {
// Start each drop statement as a new query
$sql .= 'ALTER TABLE ' . $db->quote_table($this->_original_name) . ' ' . DB::drop($type, $constraint)->compile($db) . ';';
}
}
// return the SQL.
return $sql;
}
