Content

CDbMigration

This class provides high level abstraction for changing database structure operations. It is supposed to be a base class for migrations where actual work on changing database structure happens using this class helper methods. Run() methods should be implemented with database structure changing instructions. Revert() method may be implemented if you wish to provide migration reversing functionality. By default Revert() method throws DbExceptionRevertNotImplemented exception in case of attempting to revert a migration.

You can find more information in comments below. Overrided methods can be found in corresponding base class or interface.

class CDbMigration :public virtual IDbMigration, public CReleasable
{
protected:
    IDbConnection* m_pConnection; // Connection instance. Ignored if statement is provided 
    IDbStatement* m_pStatement; // Statement instance 
    IDbQueryBuilder* m_pQueryBuilder; // Query Builder instance 

    // IDbMigration database methods 
    void CreateDatabase(const String& name, const String& charset = L"", const String& collation = L"", const bool if_not_exists = false) override; // Throw exceptions in case of error 
    void AlterDatabase(const String& name, const String& charset, const String& collation) override; // Throw exceptions in case of error 
    void DropDatabase(const String& name, const bool if_exists = false) override; // Throw exceptions in case of error 

    // IDbMigration column creation methods 
    MigrationColumn Column(const String& name) override; // Create column description object 

    // IDbMigration key creation methods 
    MigrationKey Index(const String& column, const String& name = L"", const bool& fulltext = false) override; // Create index description object 
    MigrationKey Index(const StringArray& columns, const String& name = L"", const bool& fulltext = false) override; // Create index description object 
    MigrationKey Unique(const String& column, const String& name = L"") override; // Create unique index description object 
    MigrationKey Unique(const StringArray& columns, const String& name = L"") override; // Create unique index description object 
    MigrationKey PrimaryKey(const String& column, const String& name = L"") override; // Create primary key description object 
    MigrationKey PrimaryKey(const StringArray& columns, const String& name = L"") override; // Create primary key description object 
    MigrationKey ForeignKey( // Create foreign key description object 
        const String& column,
        const String& ref_table,
        const String& ref_column,
        const String& name = L"",
        const IDbMigrationKey::RefOption& on_delete = IDbMigrationKey::RefOption::None,
        const IDbMigrationKey::RefOption& on_update = IDbMigrationKey::RefOption::None) override;
    MigrationKey ForeignKey( // Create foreign key description object 
        const StringArray& columns,
        const String& ref_table,
        const StringArray& ref_columns,
        const String& name = L"",
        const IDbMigrationKey::RefOption& on_delete = IDbMigrationKey::RefOption::None,
        const IDbMigrationKey::RefOption& on_update = IDbMigrationKey::RefOption::None) override;

    // IDbMigration table methods. All methods throw exceptions in case of error 
    void CreateTable(
        const String& name,
        const MigrationColumns& columns,
        const MigrationKeys& keys,
        const bool& if_not_exists = false,
        const String& comment = L"",
        const int64& auto_increment = std::numeric_limits<int64>::min(),
        const String& charset = L"",
        const String& collation = L"",
        const String& engine = L"") override;
    void AlterTable(const String& name, const String& charset, const String& collation = L"", const bool& convert = false) override;
    void RenameTable(const String& old_name, const String& new_name) override;
    void TruncateTable(const String& name) override;
    void DropTable(const String& name, const bool if_exists = false) override;
    void DisableKeys(const String& table) override;
    void EnableKeys(const String& table) override;

    // IDbMigration column methods. All methods throw exceptions in case of error 
    void AddColumn(const String& table, const MigrationColumn& column, const String& after = L"") override;
    void AlterColumn(const String& table, const MigrationColumn& column, const String& after = L"") override;
    void AlterColumn(const String& table, const String& old_name, const MigrationColumn& column, const String& after = L"") override;
    void RenameColumn(const String& table, const String& old_name, const String& new_name) override;
    void DropColumn(const String& table, const String& name) override;

    // IDbMigration index methods. All methods throw exceptions in case of error 
    void AddKey(const String& table, const MigrationKey& key) override;
    void RenameKey(const String& table, const String& old_name, const String& new_name) override;
    void DropKey(const String& table, const String& name) override;
    void DropPrimaryKey(const String& table, const String& name = L"") override;
public:
    // IDbMigration setters 
    IDbMigration* setConnection(IDbConnection* value) override;
    IDbMigration* setStatement(IDbStatement* value) override;
    IDbMigration* setQueryBuilder(IDbQueryBuilder* value) override;

    // IDbMigration execute methods 
    void Revert() override;

    CDbMigration(const String& name);
    CDbMigration(const String& name, IDbConnection* connection, IDbStatement *statement, IDbQueryBuilder* query_builder);
};