using Sqlite; namespace Qlite { public class Database { private string file_name; private Sqlite.Database db; private long expected_version; private Table[]? tables; private Column meta_name = new Column.Text("name") { primary_key = true }; private Column meta_int_val = new Column.Long("int_val"); private Column meta_text_val = new Column.Text("text_val"); private Table meta_table; public bool debug = false; public Database(string file_name, long expected_version) { this.file_name = file_name; this.expected_version = expected_version; meta_table = new Table(this, "_meta"); meta_table.init({meta_name, meta_int_val, meta_text_val}); } public void init(Table[] tables) { Sqlite.config(Config.SERIALIZED); int ec = Sqlite.Database.open_v2(file_name, out db, OPEN_READWRITE | OPEN_CREATE | 0x00010000); if (ec != Sqlite.OK) { error(@"SQLite error: %d - %s", db.errcode(), db.errmsg()); } this.tables = tables; start_migration(); if (debug) db.trace((message) => print(@"Qlite trace: $message\n")); } public void ensure_init() { if (tables == null) error(@"Database $file_name was not initialized, call init()"); } private void start_migration() { meta_table.create_table_at_version(expected_version); long old_version = 0; old_version = meta_table.row_with(meta_name, "version")[meta_int_val, -1]; if (old_version == -1) { foreach (Table t in tables) { t.create_table_at_version(expected_version); } meta_table.insert().value(meta_name, "version").value(meta_int_val, expected_version).perform(); } else if (expected_version != old_version) { foreach (Table t in tables) { t.create_table_at_version(old_version); } foreach (Table t in tables) { t.add_columns_for_version(old_version, expected_version); } migrate(old_version); foreach (Table t in tables) { t.delete_columns_for_version(old_version, expected_version); } if (old_version == -1) { meta_table.insert().value(meta_name, "version").value(meta_int_val, expected_version).perform(); } else { meta_table.update().with(meta_name, "=", "version").set(meta_int_val, expected_version).perform(); } } foreach (Table t in tables) { t.post(); } } internal int errcode() { return db.errcode(); } internal string errmsg() { return db.errmsg(); } internal int64 last_insert_rowid() { return db.last_insert_rowid(); } // To be implemented by actual implementation if required // new table columns are added, outdated columns are still present and will be removed afterwards public virtual void migrate(long old_version) { } public QueryBuilder select(Column[]? columns = null) { ensure_init(); return new QueryBuilder(this).select(columns); } public InsertBuilder insert() { ensure_init(); return new InsertBuilder(this); } public UpdateBuilder update(Table table) { ensure_init(); return new UpdateBuilder(this, table); } public UpsertBuilder upsert(Table table) { ensure_init(); return new UpsertBuilder(this, table); } public UpdateBuilder update_named(string table) { ensure_init(); return new UpdateBuilder.for_name(this, table); } public DeleteBuilder delete() { ensure_init(); return new DeleteBuilder(this); } public RowIterator query_sql(string sql, string[]? args = null) { ensure_init(); return new RowIterator(this, sql, args); } internal Statement prepare(string sql) { ensure_init(); Sqlite.Statement statement; if (db.prepare_v2(sql, sql.length, out statement) != OK) { error("SQLite error: %d - %s", db.errcode(), db.errmsg()); } return statement; } public void exec(string sql) throws Error { ensure_init(); if (db.exec(sql) != OK) { throw new Error(-1, 0, @"SQLite error: $(db.errcode()) - $(db.errmsg())"); } } public bool is_known_column(string table, string field) { ensure_init(); foreach (Table t in tables) { if (t.is_known_column(field)) return true; } return false; } } }