/// <summary>
/// Creates a database from a DBFill object. Used when booting up from disk.
/// </summary>
/// <param name="process">The FrostDB process.</param>
/// <param name="fill">A DBFill object (usually loaded from disk.)</param>
public Database2(Process process, DbFill fill, DbStorage storage)
{
_tables = new List <Table2>();
_process = process;
_name = fill.Schema.DatabaseName;
_databaseId = fill.Schema.DatabaseId;
_storage = storage;
_schema = fill.Schema;
FillTables(fill);
// to do: anything else?
}
/// <summary>
/// Creates a new schema file for the specified database
/// </summary>
/// <param name="schemaFileFolder">The location of the schema file folder for the Frost process</param>
/// <param name="fileExtension">The filename extension for schema files</param>
/// <param name="databaseName">The name of the database</param>
/// <param name="databaseId">The id of the database</param>
public SchemaFile(string schemaFileFolder, string fileExtension, string databaseName, int databaseId)
{
_databaseId = databaseId;
_schemaFileFolder = schemaFileFolder;
_schemaFileExtension = fileExtension;
_databaseName = databaseName;
_dbSchema = new DbSchema2();
if (DoesFileExist())
{
LoadFile();
}
else
{
CreateFile();
}
}
/// <summary>
/// Updates the local schema reference based on the current tables and columns in memory
/// </summary>
private void UpdateSchema()
{
var schema = new DbSchema2(_databaseId, _name);
_tables.ForEach(table =>
{
var tableSchema = new TableSchema2(table.TableId, table.Name, _name, _databaseId, table.Columns.Length);
int colIndx = 0;
table.Columns.ForEach(column =>
{
var columnSchema = new ColumnSchema(column.Name, column.DataType);
tableSchema.Columns[colIndx] = columnSchema;
colIndx++;
});
schema.Tables.Add(tableSchema);
});
_schema = schema;
}
/// <summary>
/// Saves the specified schema to disk
/// </summary>
/// <param name="schema">The current database schema</param>
public void Save(DbSchema2 schema)
{
_locker.EnterWriteLock();
using (var file = new StreamWriter(FileName()))
{
file.WriteLine("version " + VersionNumber.ToString());
file.WriteLine($"database { _databaseId.ToString()} { _databaseName}");
foreach (var table in schema.Tables)
{
// table tableId tableName numOfColumns
file.WriteLine($"table {table.TableId.ToString()} {table.Name} {table.Columns.Length.ToString()}");
foreach (var column in table.Columns)
{
// column columnName columnDataType
file.WriteLine($"column {column.Name} {column.DataType}");
}
}
}
_locker.ExitWriteLock();
}
/// <summary>
/// Updates the schema file on disk
/// </summary>
/// <param name="schema">The schema to save to disk</param>
public void SaveSchema(DbSchema2 schema)
{
_schema.Save(schema);
}
