📏 Schema

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

ℹ️ 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:

use Hector\Connection\Connection;
use Hector\Schema\Generator\MySQL;

$connection = new Connection('...');
$generator = new MySQL($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:

$serialized = serialize($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 🌟

📚 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

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

$generator = new MySQL($connection);
$schema = $generator->generateSchema('my_database');

foreach ($schema as $table) {
    echo "Table: " . $table->getName() . "\n";
    foreach ($table->getColumns() as $column) {
        echo "  Column: " . $column->getName() . " (" . $column->getType() . ")\n";
    }
}

This example will output the structure of your database with all tables and their columns. Great for CLI tools, documentation generators or migration scripts! 📊