Class: DuckDB::Database

Inherits:
Object
  • Object
show all
Defined in:
lib/duckdb/database.rb,
ext/duckdb/database.c

Overview

The Database class encapsulates a DuckDB database.

The usage is as follows:

require 'duckdb'

db = DuckDB::Database.open # database in memory
con = db.connect

con.query('CREATE TABLE users (id INTEGER, name VARCHAR(30))')

con.query("INSERT into users VALUES(1, 'Alice')")
con.query("INSERT into users VALUES(2, 'Bob')")
con.query("INSERT into users VALUES(3, 'Cathy')")

result = con.query('SELECT * from users')
result.each do |row|
  p row
end

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

._open(*args) ⇒ Object 



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# File 'ext/duckdb/database.c', line 46

static VALUE duckdb_database_s_open(int argc, VALUE *argv, VALUE cDuckDBDatabase) {
    rubyDuckDB *ctx;
    VALUE obj;

    char *pfile = NULL;
    VALUE file = Qnil;

    rb_scan_args(argc, argv, "01", &file);

    if (!NIL_P(file)) {
        pfile = StringValuePtr(file);
    }

    obj = allocate(cDuckDBDatabase);
    TypedData_Get_Struct(obj, rubyDuckDB, &database_data_type, ctx);
    if (duckdb_open(pfile, &(ctx->db)) == DuckDBError) {
        rb_raise(eDuckDBError, "Failed to open database"); /* FIXME */
    }
    return obj;
}

._open_ext(*args) ⇒ Object 



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# File 'ext/duckdb/database.c', line 67

static VALUE duckdb_database_s_open_ext(int argc, VALUE *argv, VALUE cDuckDBDatabase) {
    rubyDuckDB *ctx;
    VALUE obj;
    rubyDuckDBConfig *ctx_config;
    char *perror;

    char *pfile = NULL;
    VALUE file = Qnil;
    VALUE config = Qnil;

    rb_scan_args(argc, argv, "02", &file, &config);

    if (!NIL_P(file)) {
        pfile = StringValuePtr(file);
    }

    obj = allocate(cDuckDBDatabase);
    TypedData_Get_Struct(obj, rubyDuckDB, &database_data_type, ctx);
    if (!NIL_P(config)) {
        if (!rb_obj_is_kind_of(config, cDuckDBConfig)) {
            rb_raise(rb_eTypeError, "The second argument must be DuckDB::Config object.");
        }
        ctx_config = get_struct_config(config);
        if (duckdb_open_ext(pfile, &(ctx->db), ctx_config->config, &perror) == DuckDBError) {
            rb_raise(eDuckDBError, "Failed to open database %s", perror);
        }
    } else {
        if (duckdb_open(pfile, &(ctx->db)) == DuckDBError) {
            rb_raise(eDuckDBError, "Failed to open database"); /* FIXME */
        }
    }
    return obj;
}

.open(dbpath = nil, config = nil) ⇒ Object

Opens database. The first argument is DuckDB database file path to open. If there is no argument, the method opens DuckDB database in memory. The method yields block if block is given.

DuckDB::Database.open('duckdb_database.db') #=> DuckDB::Database

DuckDB::Database.open #=> opens DuckDB::Database in memory.

DuckDB::Database.open do |db|
  con = db.connect
  con.query('CREATE TABLE users (id INTEGER, name VARCHAR(30))')
end



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# File 'lib/duckdb/database.rb', line 41

def open(dbpath = nil, config = nil)
  db = _db_open(dbpath, config)
  return db unless block_given?

  begin
    yield db
  ensure
    db.close
  end
end

Instance Method Details

#close ⇒ DuckDB::Database

closes DuckDB database.

Returns:



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# File 'ext/duckdb/database.c', line 111

static VALUE duckdb_database_close(VALUE self) {
    rubyDuckDB *ctx;
    TypedData_Get_Struct(self, rubyDuckDB, &database_data_type, ctx);
    close_database(ctx);
    return self;
}

#connect ⇒ Object

connects database.

The method yields block and disconnects the database if block given

db = DuckDB::Database.open

con = db.connect # => DuckDB::Connection

db.connect do |con|
  con.query('CREATE TABLE users (id INTEGER, name VARCHAR(30))')
end



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# File 'lib/duckdb/database.rb', line 74

def connect
  conn = _connect
  return conn unless block_given?

  begin
    yield conn
  ensure
    conn.disconnect
  end
end