/**
* Returns a MySqlComparisonSchema reflecting the schema of a database table.
*
* @param $tableName
* @return MySqlComparisonSchema
*/
public static function fromTable($tableName)
{
$repos = Repository::getDefaultRepositoryClassName();
// Get the create table syntax for the table - we'll analyse this and build our schema accordingly.
$row = $repos::returnFirstRow("SHOW CREATE TABLE {$tableName}");
$sql = $row["Create Table"];
$lines = explode("\n", $sql);
// First and last lines aren't needed
$lines = array_slice($lines, 1, -1);
$comparisonSchema = new MySqlComparisonSchema();
foreach ($lines as $line) {
$line = trim($line);
// If the line starts with a back tick we have a column
if ($line[0] == "`") {
$default = null;
preg_match("/`([^`]+)`/", rtrim($line, ','), $matches);
$name = $matches[1];
$comparisonSchema->columns[$name] = rtrim(trim($line), ",");
} else {
$words = explode(" ", $line);
$indexKeywords = ["PRIMARY", "KEY", "UNIQUE"];
if (in_array($words[0], $indexKeywords)) {
$comparisonSchema->indexes[] = preg_replace('/\\s+/', ' ', rtrim(trim($line), ","));
}
}
}
return $comparisonSchema;
}
/**
* Creates the table in the back end data store.
*/
private function createTable()
{
$sql = "CREATE TABLE " . $this->schemaName . " (";
$definitions = [];
foreach ($this->columns as $columnName => $column) {
// The column might be using a more generic type for it's storage.
$storageColumns = $column->createStorageColumns();
foreach ($storageColumns as $storageColumn) {
// And if so that column will be a generic column type - we need to upgrade it.
$storageColumn = $storageColumn->getRepositorySpecificColumn("MySql");
$definitions[] = $storageColumn->getDefinition();
}
}
foreach ($this->indexes as $indexName => $index) {
$definitions[] = $index->getDefinition();
}
$sql .= implode(",", $definitions);
$sql .= "\n\t\t\t)";
$repos = Repository::getDefaultRepositoryClassName();
$repos::executeStatement($sql);
}