--- breadcrumb: - Components - Schema summary-order: ;5 --- # 📏 Schema > ℹī¸ **Note**: While schemas are part of the **Hector ORM** ecosystem, they are available as a standalone package: > [`hectororm/schema`](https://github.com/hectororm/schema). > You can find it on > [Packagist](https://packagist.org/packages/hectororm/schema). > You can use them independently of the ORM, in any PHP application. 🎉 **Hector Schema** is the schema introspection and metadata module of **Hector ORM**. It provides a simple and consistent API to explore and manage your database structure. While tightly integrated with **Hector ORM**, this package is entirely independent and can be used on its own. ## 🌐 DBMS Compatibility | DBMS | Version | Compatibility | |---------|:-------:|:-------------:| | MySQL | 8.4 | ✔ | | MySQL | 8.0 | ✔ | | MySQL | 5.7 | ✔ | | MariaDB | 11.7 | ✔ | | MariaDB | 11.4 | ✔ | | MariaDB | 10.11 | ✔ | | MariaDB | 10.6 | ✔ | | MariaDB | 10.5 | ✔ | | Sqlite | 3.x | ✔ | > ℹī¸ **Note**: Versions listed are actively tested. Older versions may work but are not officially supported. > Know of a DBMS version not listed here but works fine? Contributions are welcome — open a PR! ## 🔧 Usage ### Generate a schema The schema generator reads your DB structure and returns rich PHP objects that describe it: ```php use Hector\Connection\Connection; use Hector\Schema\Generator\MySQL; use Hector\Schema\Generator\Sqlite; // MySQL / MariaDB $connection = new Connection('mysql:host=localhost;dbname=mydb', 'user', 'pass'); $generator = new MySQL($connection); // SQLite $connection = new Connection('sqlite:/path/to/database.db'); $generator = new Sqlite($connection); $schema = $generator->generateSchema('schema_name'); // Returns a `Hector\Schema\Schema` object $container = $generator->generateSchemas('schema1_name', 'schema2_name'); // Returns a `Hector\Schema\SchemaContainer` object ``` Available generators: * `Hector\Schema\Generator\MySQL` — for MySQL and MariaDB * `Hector\Schema\Generator\Sqlite` — for SQLite > 💡 **Tip**: You can use different generators for different environments (e.g., dev SQLite, prod MySQL). ### 📁 Caching schemas Schema generation can be expensive for large databases. This library does **not** include built-in caching, as caching strategies vary widely. Instead, you can serialize schema objects and restore them later: ```php $serialized = serialize($schema); file_put_contents('cache/schema.ser', $serialized); // Later... $schema = unserialize(file_get_contents('cache/schema.ser')); ``` Inheritance and references between objects are preserved during (de)serialization. This makes caching simple and flexible — ideal for integrating into your own caching logic 🌟 > ⚠ī¸ **Warning**: Ensure your cache is invalidated when the database schema changes (e.g., after migrations). --- ## 📚 API Reference This section covers the main classes used to explore database schemas. ### `Hector\Schema\SchemaContainer` A container for multiple schemas. Useful when your application interacts with multiple databases or schemas. **Key methods:** * `getSchemas(?string $connection = null): Generator` * `hasSchema(string $name, ?string $connection = null): bool` * `getSchema(string $name, ?string $connection = null): Schema` * `hasTable(string $name, ?string $schemaName = null, ?string $connection = null): bool` * `getTable(string $name, ?string $schemaName = null, ?string $connection = null): Table` ```php // Get table from default schema $usersTable = $container->getTable('users'); // Get table from specific schema $usersTable = $container->getTable('users', 'my_database'); // Get table from specific schema and connection $usersTable = $container->getTable('users', 'my_database', 'replica'); ``` > This class is iterable: `foreach ($container as $schema)` will yield `Hector\Schema\Schema` objects. ### `Hector\Schema\Schema` Represents a single schema (i.e., database). **Key methods:** * `getName(bool $quoted = false): string` * `getCharset(): string` * `getCollation(): string` * `getTables(): Generator` * `hasTable(string $name): bool` * `getTable(string $name): Table` * `getContainer(): ?SchemaContainer` > This class is also iterable: `foreach ($schema as $table)` yields `Hector\Schema\Table` objects. ### `Hector\Schema\Table` Represents a table and its structure. **Key methods:** * Identification: * `getSchemaName(bool $quoted = false): string` * `getName(bool $quoted = false): string` * `getFullName(bool $quoted = false): string` * Metadata: * `getType(): string` * `getCharset(): ?string` * `getCollation(): ?string` * Columns: * `getColumns(): Generator` * `getColumnsName(bool $quoted = false, ?string $tableAlias = null): array` * `hasColumn(string $name): bool` * `getColumn(string $name): Column` * `getAutoIncrementColumn(): ?Column` * Indexes: * `getIndexes(?string $type = null): Generator` * `hasIndex(string $name): bool` * `getIndex(string $name): Index` * `getPrimaryIndex(): ?Index` * Foreign Keys: * `getForeignKeys(Table $table = null): Generator` * Other: * `getSchema(): Schema` ### `Hector\Schema\Column` Represents a column in a table. **Key methods:** * Identification: * `getName(bool $quoted = false, ?string $tableAlias = null): string` * `getFullName(bool $quoted = false): string` * Metadata: * `getPosition(): int` * `getDefault(): mixed` * `isNullable(): bool` * `getType(): string` * `isAutoIncrement(): bool` * `getMaxlength(): ?int` * `getNumericPrecision(): ?int` * `getNumericScale(): ?int` * `isUnsigned(): bool` * `getCharset(): ?string` * `getCollation(): ?string` * Other: * `getTable(): Table` * `isPrimary(): bool` ### `Hector\Schema\Index` Represents a table index. **Key methods:** * `getName(): string` * `getType(): string` * `getColumnsName(bool $quoted = false, ?string $tableAlias = null): array` * `getTable(): Table` * `getColumns(): array` * `hasColumn(Column $column): bool` ### `Hector\Schema\ForeignKey` Represents a foreign key constraint. **Key methods:** * `getName(): string` * `getColumnsName(bool $quoted = false, ?string $tableAlias = null): array` * `getReferencedSchemaName(): string` * `getReferencedTableName(): string` * `getReferencedColumnsName(bool $quoted = false, ?string $tableAlias = null): array` * `getUpdateRule(): string` * `getDeleteRule(): string` * `getTable(): Table` * `getColumns(): Generator` * `getReferencedTable(): ?Table` * `getReferencedColumns(): Generator` --- ## 🎓 Example: Basic schema introspection ```php $generator = new MySQL($connection); $schema = $generator->generateSchema('my_database'); foreach ($schema as $table) { echo "Table: " . $table->getName() . "\n"; // Columns foreach ($table->getColumns() as $column) { echo " Column: " . $column->getName() . " (" . $column->getType() . ")"; echo $column->isNullable() ? " NULL" : " NOT NULL"; echo $column->isPrimary() ? " [PK]" : ""; echo "\n"; } // Indexes foreach ($table->getIndexes() as $index) { echo " Index: " . $index->getName() . " (" . $index->getType() . ")"; echo " on [" . implode(', ', $index->getColumnsName()) . "]\n"; } // Foreign keys foreach ($table->getForeignKeys() as $fk) { echo " FK: " . $fk->getName(); echo " [" . implode(', ', $fk->getColumnsName()) . "]"; echo " -> " . $fk->getReferencedTableName(); echo " [" . implode(', ', $fk->getReferencedColumnsName()) . "]\n"; } echo "\n"; } ``` This example will output the structure of your database with all tables, columns, indexes and foreign keys. Great for CLI tools, documentation generators or migration scripts! 📊