Keywords: ODBC Binding for Ruby

# Ruby ODBC Reference

Last update: Wed, 13 March 2013

## ODBC

The module to encapsulate the Ruby ODBC binding.

### module functions:

`datasources`
  Returns an array of ODBC::DSNs, i.e. all known data source names.
`drivers`
  Returns an array of ODBC::Drivers, i.e. all known ODBC drivers.
`error`
  Returns the last error messages (String array) or nil. The layout of the warning/error messages is described here. Retrieving this message as well as subsequent succeeding ODBC method invocations do not clear the message. Use the `clear_error` method for that purpose.
`info`
  Returns the last driver/driver manager warning messages (String array) or nil. The layout of the warning/error messages is described here. Retrieving this message as well as subsequent succeeding ODBC method invocations do not clear the message. Use the `clear_error` method for that purpose.
`clear_error`
  Resets the last driver/driver manager error and warning messages to nil.
`raise(value)`
  Raises an ODBC::Error exception with String error message value.
`newenv`
  Returns a new ODBC::Environment.
`connection_pooling[=value]`
  Gets or sets the process-wide connection pooling attribute.
`to_time(timestamp)`
`to_time(date,[time])`
`to_time(time,[date])`
  Creates a `Time` object from the specified arguments, which must be ODBC::Date, ODBC::Time, or ODBC::TimeStamp objects.
`to_date(timestamp)`
`to_date(date)`
  Creates a `Date` object from the specified arguments, which must be ODBC::Date, or ODBC::TimeStamp objects.
`connect(dsn,[user,passwd]) [{|dbc| block}]`
  If no block is specified, a connection to the given data source is established and a ODBC::Database object is returned, identifying that connection. Otherwise, the block is executed with the database object. When the block is finished, the connection is automatically released. Options are:
    dsn: Data source name (String or ODBC::DSN)
    user: Login user name (String)
    passwd: Login password (String)

### constants:

The boolean constant UTF8 reports the character encoding of the module. If it is `true`, the UTF-8 variant of the module is in use, and string data is automatically converted to/from Unicode.

Some constants of the ODBC API are defined in order to set connection options, to deal with SQL data types, and to obtain database meta data.

Cursor behaviour:
  SQL_CURSOR_FORWARD_ONLY, SQL_CURSOR_KEYSET_DRIVEN, SQL_CURSOR_DYNAMIC, SQL_CURSOR_STATIC
Concurrency (transactions):
  SQL_CONCUR_READ_ONLY, SQL_CONCUR_LOCK, SQL_CONCUR_ROWVER, SQL_CONCUR_VALUES
Fetch direction:
  SQL_FETCH_NEXT, SQL_FETCH_FIRST, SQL_FETCH_LAST, SQL_FETCH_PRIOR, SQL_FETCH_ABSOLUTE, SQL_FETCH_RELATIVE
Data types:
  SQL_UNKNOWN_TYPE, SQL_CHAR, SQL_NUMERIC, SQL_DECIMAL, SQL_INTEGER, SQL_SMALLINT, SQL_FLOAT, SQL_REAL, SQL_DOUBLE, SQL_VARCHAR, SQL_DATETIME, SQL_DATE, SQL_TYPE_DATE, SQL_TIME, SQL_TYPE_TIME, SQL_TIMESTAMP, SQL_TYPE_TIMESTAMP, SQL_LONGVARCHAR, SQL_BINARY, SQL_VARBINARY, SQL_LONGVARBINARY, SQL_BIGINT, SQL_TINYINT, SQL_BIT, SQL_GUID
Parameter related:
  SQL_PARAM_TYPE_UNKNOWN, SQL_PARAM_INPUT, SQL_PARAM_OUTPUT, SQL_PARAM_INPUT_OUTPUT, SQL_DEFAULT_PARAM SQL_RETURN_VALUE
Procedure related:
  SQL_RESULT_COL, SQL_PT_UNKNOWN, SQL_PT_PROCEDURE, SQL_PT_FUNCTION
Environment attributes:
  SQL_CP_OFF, SQL_CP_ONE_PER_DRIVER, SQL_CP_ONE_PER_HENV, SQL_CP_DEFAULT, SQL_CP_STRICT_MATCH, SQL_CP_RELAXED_MATCH, SQL_CP_MATCH_DEFAULT, SQL_OV_ODBC2, SQL_OV_ODBC3
Info types for `ODBC::Database.get_info` yielding integer results:
  SQL_ACTIVE_ENVIRONMENTS, SQL_ACTIVE_CONNECTIONS, SQL_ACTIVE_STATEMENTS, SQL_ASYNC_MODE, SQL_CATALOG_LOCATION, SQL_CONCAT_NULL_BEHAVIOR, SQL_CORRELATION_NAME, SQL_CURSOR_COMMIT_BEHAVIOR, SQL_CURSOR_ROLLBACK_BEHAVIOR, SQL_CURSOR_SENSITIVITY, SQL_DDL_INDEX, SQL_DEFAULT_TXN_ISOLATION, SQL_DRIVER_HDBC, SQL_DRIVER_HENV, SQL_DRIVER_HDESC, SQL_DRIVER_HLIB, SQL_DRIVER_HSTMT, SQL_FILE_USAGE, SQL_GROUP_BY, SQL_IDENTIFIER_CASE, SQL_MAX_ASYNC_CONCURRENT_STATEMENTS, SQL_MAX_BINARY_LITERAL_LEN, SQL_MAX_CATALOG_NAME_LEN, SQL_MAX_CHAR_LITERAL_LEN, SQL_MAX_COLUMN_NAME_LEN, SQL_MAX_COLUMNS_IN_GROUP_BY, SQL_MAX_COLUMNS_IN_INDEX, SQL_MAX_COLUMNS_IN_ORDER_BY, SQL_MAX_COLUMNS_IN_SELECT, SQL_MAX_COLUMNS_IN_TABLE, SQL_MAX_CONCURRENT_ACTIVITIES, SQL_MAX_CURSOR_NAME_LEN, SQL_MAX_DRIVER_CONNECTIONS, SQL_MAX_IDENTIFIER_LEN, SQL_MAX_INDEX_SIZE, SQL_MAX_OWNER_NAME_LEN, SQL_MAX_PROCEDURE_NAME_LEN, SQL_MAX_QUALIFIER_NAME_LEN, SQL_MAX_ROW_SIZE, SQL_MAX_SCHEMA_NAME_LEN, SQL_MAX_STATEMENT_LEN, SQL_MAX_TABLE_NAME_LEN, SQL_MAX_TABLES_IN_SELECT, SQL_MAX_USER_NAME_LEN, SQL_NON_NULLABLE_COLUMNS, SQL_NULL_COLLATION, SQL_ODBC_API_CONFORMANCE, SQL_ODBC_INTERFACE_CONFORMANCE, SQL_ODBC_SAG_CLI_CONFORMANCE, SQL_ODBC_SQL_CONFORMANCE, SQL_PARAM_ARRAY_ROW_COUNTS, SQL_PARAM_ARRAY_SELECTS, SQL_QUALIFIER_LOCATION, SQL_QUOTED_IDENTIFIER_CASE, SQL_SQL_CONFORMANCE, SQL_TXN_CAPABLE
Info types for `ODBC::Database.get_info` yielding bitmasks (integer results):
  SQL_AGGREGATE_FUNCTIONS, SQL_ALTER_DOMAIN, SQL_ALTER_TABLE, SQL_BATCH_ROW_COUNT, SQL_BATCH_SUPPORT, SQL_BOOKMARK_PERSISTENCE, SQL_CATALOG_USAGE, SQL_CONVERT_BINARY, SQL_CONVERT_BIT, SQL_CONVERT_CHAR, SQL_CONVERT_GUID, SQL_CONVERT_DATE, SQL_CONVERT_DECIMAL, SQL_CONVERT_DOUBLE, SQL_CONVERT_FLOAT, SQL_CONVERT_FUNCTIONS, SQL_CONVERT_INTEGER, SQL_CONVERT_INTERVAL_YEAR_MONTH, SQL_CONVERT_INTERVAL_DAY_TIME, SQL_CONVERT_LONGVARBINARY, SQL_CONVERT_LONGVARCHAR, SQL_CONVERT_NUMERIC, SQL_CONVERT_REAL, SQL_CONVERT_SMALLINT, SQL_CONVERT_TIME, SQL_CONVERT_TIMESTAMP, SQL_CONVERT_TINYINT, SQL_CONVERT_VARBINARY, SQL_CONVERT_VARCHAR, SQL_CONVERT_WCHAR, SQL_CONVERT_WLONGVARCHAR, SQL_CONVERT_WVARCHAR, SQL_CREATE_ASSERTION, SQL_CREATE_CHARACTER_SET, SQL_CREATE_COLLATION, SQL_CREATE_DOMAIN, SQL_CREATE_SCHEMA, SQL_CREATE_TABLE, SQL_CREATE_TRANSLATION, SQL_CREATE_VIEW, SQL_DATETIME_LITERALS, SQL_DROP_ASSERTION, SQL_DROP_CHARACTER_SET, SQL_DROP_COLLATION, SQL_DROP_DOMAIN, SQL_DROP_SCHEMA, SQL_DROP_TABLE, SQL_DROP_TRANSLATION, SQL_DROP_VIEW, SQL_DTC_TRANSITION_COST, SQL_DYNAMIC_CURSOR_ATTRIBUTES1, SQL_DYNAMIC_CURSOR_ATTRIBUTES2, SQL_FETCH_DIRECTION, SQL_FORWARD_ONLY_CURSOR_ATTRIBUTES1, SQL_FORWARD_ONLY_CURSOR_ATTRIBUTES2, SQL_GETDATA_EXTENSIONS, SQL_KEYSET_CURSOR_ATTRIBUTES1, SQL_KEYSET_CURSOR_ATTRIBUTES2, SQL_INDEX_KEYWORDS, SQL_INFO_SCHEMA_VIEWS, SQL_INSERT_STATEMENT, SQL_LOCK_TYPES, SQL_NUMERIC_FUNCTIONS, SQL_OJ_CAPABILITIES, SQL_OWNER_USAGE, SQL_POS_OPERATIONS, SQL_POSITIONED_STATEMENTS, SQL_QUALIFIER_USAGE, SQL_SCHEMA_USAGE, SQL_SCROLL_CONCURRENCY, SQL_SCROLL_OPTIONS, SQL_SQL92_DATETIME_FUNCTIONS, SQL_SQL92_FOREIGN_KEY_DELETE_RULE, SQL_SQL92_FOREIGN_KEY_UPDATE_RULE, SQL_SQL92_GRANT, SQL_SQL92_NUMERIC_VALUE_FUNCTIONS, SQL_SQL92_PREDICATES, SQL_SQL92_RELATIONAL_JOIN_OPERATORS, SQL_SQL92_REVOKE, SQL_SQL92_ROW_VALUE_CONSTRUCTOR, SQL_SQL92_STRING_FUNCTIONS, SQL_SQL92_VALUE_EXPRESSIONS, SQL_STANDARD_CLI_CONFORMANCE, SQL_STATIC_CURSOR_ATTRIBUTES1, SQL_STATIC_CURSOR_ATTRIBUTES2, SQL_STATIC_SENSITIVITY, SQL_STRING_FUNCTIONS, SQL_SUBQUERIES, SQL_SYSTEM_FUNCTIONS, SQL_TIMEDATE_ADD_INTERVALS, SQL_TIMEDATE_DIFF_INTERVALS, SQL_TIMEDATE_FUNCTIONS, SQL_TXN_ISOLATION_OPTION, SQL_UNION
Info types for `ODBC::Database.get_info` yielding strings:
  SQL_ACCESSIBLE_PROCEDURES, SQL_ACCESSIBLE_TABLES, SQL_CATALOG_NAME, SQL_CATALOG_NAME_SEPARATOR, SQL_CATALOG_TERM, SQL_COLLATION_SEQ, SQL_COLUMN_ALIAS, SQL_DATA_SOURCE_NAME, SQL_DATA_SOURCE_READ_ONLY, SQL_DATABASE_NAME, SQL_DBMS_NAME, SQL_DBMS_VER, SQL_DESCRIBE_PARAMETER, SQL_DM_VER, SQL_DRIVER_NAME, SQL_DRIVER_ODBC_VER, SQL_DRIVER_VER, SQL_EXPRESSIONS_IN_ORDERBY, SQL_IDENTIFIER_QUOTE_CHAR, SQL_INTEGRITY, SQL_KEYWORDS, SQL_LIKE_ESCAPE_CLAUSE, SQL_MAX_ROW_SIZE_INCLUDES_LONG, SQL_MULT_RESULT_SETS, SQL_MULTIPLE_ACTIVE_TXN, SQL_NEED_LONG_DATA_LEN, SQL_ODBC_SQL_OPT_IEF, SQL_ODBC_VER, SQL_ORDER_BY_COLUMNS_IN_SELECT, SQL_OUTER_JOINS, SQL_OWNER_TERM, SQL_PROCEDURE_TERM, SQL_PROCEDURES, SQL_QUALIFIER_NAME_SEPARATOR, SQL_QUALIFIER_TERM, SQL_ROW_UPDATES, SQL_SCHEMA_TERM, SQL_SEARCH_PATTERN_ESCAPE, SQL_SERVER_NAME, SQL_SPECIAL_CHARACTERS, SQL_TABLE_TERM, SQL_USER_NAME, SQL_XOPEN_CLI_YEAR
Options for `ODBC::Database.get_option`, `ODBC::Database.set_option`, `ODBC::Statement.get_option`, and `ODBC::Statement.set_option` yielding integers:
  SQL_AUTOCOMMIT, SQL_CONCURRENCY, SQL_QUERY_TIMEOUT, SQL_MAX_ROWS, SQL_MAX_LENGTH, SQL_NOSCAN, SQL_ROWSET_SIZE, SQL_CURSOR_TYPE

## ODBC::Object

The class to represent the root of all other ODBC related objects.

### super class:

`Object`

### methods:

`error`
  Returns the last error message (String) or nil. For further information see ODBC::error.
`info`
  Returns the last driver/driver manager warning messages (String array) or nil. For further information see ODBC::error.
`clear_error`
  Resets the last driver/driver manager error and warning messages to nil.
`raise(value)`
  Raises an ODBC::Error exception with String error message value.

### singleton methods:

`error`
  Returns the last error message (String array) or nil. For further information see ODBC::error.
`info`
  Returns the last driver/driver manager warning messages (String array) or nil. For further information see ODBC::error.
`clear_error`
  Resets the last driver/driver manager error and warning messages to nil.
`raise(value)`
  Raises an ODBC::Error exception with String error message value.

## ODBC::Environment

The class to represent the environment for ODBC::Databases.

### super class:

`ODBC::Object`

### methods:

`connect(dsn,[user,passwd])`
  Connects to an ODBC data source and returns a ODBC::Database object. Options are:
    dsn: Data source name (String or ODBC::DSN)
    user: Login user name (String)
    passwd: Login password (String)
`environment`
  Returns the ODBC::Environment of the object.
`commit`
  Commits the current transaction.
`rollback`
  Rollbacks the current transaction.
`transaction {|env| block}`
  First commits the current transaction, then executes the given block where the paramater is the object itself (an environment or a database connection). If the block raises an exception, the transaction is rolled back, otherwise committed.
`connection_pooling[=value]`
  Gets or sets the connection pooling attribute of the environment.
`cp_match[=value]`
  Gets or sets the connection pooling match attribute of the environment.
`odbc_version[=value]`
  Gets or sets the ODBC version attribute of the environment.

### singleton methods:

`new`
  Returns a new ODBC::Environment object.

## ODBC::Database

The class to represent a connection to an ODBC data source.

When underlying ODBC SQL functions report an error, an ODBC::Error exception with a corresponding error message from the ODBC driver manager and/or driver is raised.

### super class:

`ODBC::Environment`

### methods:

`connected?`
  Returns `true` when the object is in connected state, false otherwise.
`drvconnect(drv)`
  Connect to a data source specified by drv (ODBC::Driver).
`disconnect(no_drop=false)`
  Disconnects from the data source, all active statements for the connection are dropped except when the no_drop argument is true. The method returns true when the connection was released, false otherwise.
`newstmt`
  Returns a new ODBC::Statement object without preparing or executing a SQL statement. This allows to use `ODBC::Statement.set_option` to set special options on the statement before actual execution.
`tables([pattern])`
  Returns an ODBC::Statement with information of all or some (pattern String given) tables of the data source.
`columns([table[,column]])`
  Returns an ODBC::Statement with column information of the given table (String) and optional column (String).
`indexes([table[,unique]])`
  Returns an ODBC::Statement with index information of the given table (String). If unique is given and true, information for unique indexes only is returned.
`types([tcode])`
  Returns an ODBC::Statement with type information of the numeric SQL type tcode or all types if tcode is omitted.
`primary_keys([table])`
  Returns an ODBC::Statement with primary key information of the given table (String).
`foreign_keys([table])`
  Returns an ODBC::Statement with foreign key information of the given table (String).
`table_privileges([table])`
  Returns an ODBC::Statement with owner/right information of the given table (String).
`procedures([p])`
  Returns an ODBC::Statement with information about stored procedures.
`procedure_columns([p])`
  Returns an ODBC::Statement with information about stored procedures.
`special_columns([table[,id,scope]])`
  Returns an ODBC::Statement with column information of the given table (String) indicating the optimal unique or identifying columns. id may be specified as `ODBC::SQL_BEST_ROWID` or `ODBC::SQL_ROW_VER`. scope may be specified as `ODBC::SQL_SCOPE_CURROW`, `ODBC::SQL_SCOPE_TRANSACTION`, or `ODBC::SQL_SCOPE_SESSION`. If omitted the defaults are `ODBC::SQL_BEST_ROWID` and `ODBC::SQL_SCOPE_CURROW`.
`get_info(info_type[,sql_type])`
  Retrieves database meta data according to info_type and returns numbers or strings. info_type may be specified as integer or string. To force interpretation of the return value of the underlying ODBC function `SQLGetInfo()` as a specific Ruby type the optional parameter sql_type can be given as e.g. `ODBC::SQL_SMALLINT` (yielding integer), `ODBC::SQL_INTEGER` (yielding integer), and `ODBC::SQL_CHAR` (yielding string).
`run(sql[,args...])`
  Prepares and executes the query specified by sql with parameters bound from args and returns an ODBC::Statement or nil, if the query did not produce a result set, e.g. when executing SQL insert, delete, or update statements.
`do(sql[,args...])`
  Prepares and executes the query as in `run`, but returns the number of result rows and automatically drops the statement. Useful for SQL insert, delete, or update statements.
`prepare(sql)`
  Prepares the query specified by sql and returns an ODBC::Statement.
`proc(sql,[type,size[,n=1]]) {|stmt| block}`
  Prepares the query specified by sql within a ODBCProc and returns that procedure. When the procedure is called, the statement is executed with the procedure's arguments bound to the statement's parameters and the statement is bound as parameter in the block, e.g.

      # add customer given name and id
      # and return number of affected rows

      addcust = dbc.proc("insert into customer values(?, ?)") { |stmt|
          stmt.nrows
      }

      addcust.call("J.R. User", 9999)

      # alternative to call: addcust["J.R. User", 9999]

  The optional arguments type, size, and n, make the n-th statement parameter into an output parameter with that given ODBC data type and size. That statement parameter must be omitted when the ODBCProc is called. This can be useful for wrapping stored procedures, e.g.

      # wrap statement with output parameter

      aproc = dbc.proc("{ ? = call stored_proc(?) }", ODBC::SQL_INTEGER, 4) {}

      # call this statement/procedure, output parameter is result

      result = aproc.call(99)

      # alternative to call: result = aproc[99]

  Finalization of an ODBCProc can be done according to this code snippet

      # aproc is wrapped statement, finalize it now

      aproc.statement.drop

`get_option(option)`
  Gets a connection level option. option can be a module constant, e.g. SQL_MAX_ROWS, a number, or a string. This method returns the integer value of that option.
`set_option(option,intval)`
  Sets a connection level option. option can be a module constant, e.g. SQL_MAX_ROWS, a number, or a string. The second parameter intval can be used to set driver-specific statement options.
`autocommit[=bool]`
  Sets or queries the autocommit option of the connection.
`concurrency[=intval]`
  Sets or queries the concurrency mode of cursors opened on the connection.
`maxrows[=intval]`
  Sets or queries the maximum rows returned in result sets from the connection.
`timeout[=intval]`
  Sets or queries the number of seconds to wait for queries to execute on the connection before returning.
`maxlength[=intval]`
  Sets or queries the maximum amount of data that will be returned from a character or binary column.
`cursortype[=intval]`
  Sets or queries the cursor type used for fetches.
`noscan[=bool]`
  Sets or queries whether the driver scans SQL strings for ODBC escape clauses.
`rowsetsize`
  Returns the number of rows in a rowset fetched internally by a call o SQLExtendedFetch (hardcoded to 1).
`ignorecase[=bool]`
  Sets or queries the uppercase conversion for column names. If turned on (bool is true), ODBC::Statements created by database methods will report column names in ODBC::Column or in the statement fetch methods as uppercase strings. Otherwise (the default) column names are passed unmodified.
`drop_all`
  Releases the resources of all open ODBC::Statements in this database connection.
`use_time[=bool]`
  Sets or queries the mapping of SQL_DATE, SQL_TIME, and SQL_TIMESTAMP data types to Ruby objects. When true, SQL_DATE is mapped to Ruby Date objects, SQL_TIME and SQL_TIMESTAMP are mapped to Ruby Time objects. Otherwise (default) ODBC::Date, ODBC::Time, and ODBC::TimeStamp are used.
`use_utc[=bool]`
  Sets or queries the timezone applied on SQL_DATE, SQL_TIME, and SQL_TIMESTAMP data types to Ruby objects. When true, Ruby Date and Time objects are represented in UTC, when false (default) in the local timezone.
`use_sql_column_name[=bool]`
  Sets or queries the flag controlling how column names are read from the data source. When false (default), the ODBC API `SQLColAttributes(SQL_COLUMN_LABEL)` is used, otherwise `SQLColAttributes(SQL_COLUMN_NAME)` is used.

### singleton methods:

`new`
  Creates an unconnected ODBC object, e.g. for a later `drvconnect` method call.
`new(dsn,[user,passwd])`
  Connect to an ODBC data source. Options are:
    dsn: Data source name (String or ODBC::DSN)
    user: Login user name (String)
    passwd: Login password (String)

### Remarks:

The `run`, `prepare`, `do`, and info methods (e.g. `tables`) can be invoked with a block. In this case the block is executed with the ODBC::Statement as parameter. The `run` and `do` methods use the ODBC API function `SQLExecDirect()` when the SQL statement has no parameters.

## ODBC::Statement

The class to represent a query and its query result. The object of this class is created as the result of every query. You may need to invoke the `close` or `drop` methods for the finished object for better memory performance.

When underlying ODBC SQL functions report an error, an ODBC::Error exception with a corresponding error message from the ODBC driver manager and/or driver is raised.

ODBC to Ruby type mapping:

ODBC | Ruby
--- | ---
SQL_SMALLINT, SQL_INTEGER, SQL_TINYINT, SQL_BIT | T_FIXNUM, T_BIGNUM
SQL_FLOAT, SQL_DOUBLE, SQL_REAL | T_FLOAT
SQL_DATE, SQL_TYPE_DATE | ODBC::Date or Date, see ODBC::Database.use_time
SQL_TIME, SQL_TYPE_TIME | ODBC::Time or Time, see ODBC::Database.use_time
SQL_TIMESTAMP, SQL_TYPE_TIMESTAMP | ODBC::TimeStamp or Time, see ODBC::Database.use_time
all others | T_STRING

### super class:

`ODBC::Database`

### mixins:

`Enumerable`

### methods:

`cancel`
  Cancel and close the ODBC::Statement.
`close`
  Close the ODBC::Statement.
`drop`
  Close and free the ODBC::Statement.
`column(n)`
  Returns information of the n-th column of the query result as ODBC::Column.
`columns(as_ary=false)`
  Returns a hash of column information keyed by column names (Strings) of the query result. If as_ary is true, an array is returned. In both cases the elements are ODBC::Columns. If the hash keys happen to be not unique later columns get their column number appended, e.g. `FOOBAR`, `FOOBAR#1`.
`columns {|col| block}`
  Iterates over the columns of the query result with col bound to each ODBC::Column.
`ncols`
  Returns the number of columns of the query result.
`nrows`
  Returns the number of rows of the query result.
`cursorname[=name]`
  Returns or sets the cursor name of the statement.
`ignorecase[=bool]`
  Same as `ODBC::Database.ignorecase` but affecting this statement only. Inherited by the current state of the ODBC::Database at the time the statement is created.
`fetch`
  Returns the next row of the query result as an array.
`fetch_first`
  Returns the first row of the query result as an array.
`fetch_scroll(direction, offset=1)`
  Returns the row addressed by direction, e.g. `SQL_FETCH_LAST` as an array. offset is used for `SQL_FETCH_RELATIVE` and `SQL_FETCH_ABSOLUTE`.
`fetch_many(count)`
  Returns an array of the next count rows of the query result, where each row is an array.
`fetch_all`
  Same as `fetch_many` except that all remaining rows are returned.
`fetch_hash(with_table_names=false,use_sym=false)`
  Returns the next row of the query result as a hash keyed by column names. If with_table_names is true, the keys are combined table/column names. For uniqueness of keys the same rules as in the `columns` method are applied. If use_sym is true, the keys are formed by intern'ing the (table and) column names. Alternatively, one hash argument can be presented to `fetch_hash`, e.g. `{ :key => :Symbol, :table_names => false }` or `{ :key => :String, :table_names => true }` or `{ :key => :Fixnum }`.
`each {|row| block}`
  Iterates over the query result, performing a `fetch` for each row.
`each_hash(with_table_names=false,use_sym=false) {|row| block}`
  Iterates over the query result, performing a `fetch_hash` for each row. The same rules for arguments as in `fetch_hash` apply.
`execute([args...])`
  Binds args to current query and executes it.
`run(sql[,args...])`
  Prepares and executes the query specified by sql with parameters bound from args.
`prepare(sql)`
  Prepares the query specified by sql.
`more_results`
  Returns true and switches over to the next result set, if the query produced more than one result set. Otherwise returns false.
`get_option(option)`
  Gets a statement level option. option can be a module constant, e.g. SQL_MAX_ROWS, a number, or a string. This method returns the integer value of that option.
`set_option(option,intval)`
  Sets a statement level option. option can be a module constant, e.g. SQL_MAX_ROWS, a number, or a string. The second parameter intval can be used to set driver-specific statement options.
`concurrency[=intval]`
  Sets or queries the concurrency mode of cursors opened on the statement.
`maxrows[=intval]`
  Sets or queries the maximum rows returned by the statement.
`timeout[=intval]`
  Sets or queries the number of seconds to wait for the statement to execute before returning.
`maxlength[=intval]`
  Sets or queries the maximum amount of data that will be returned from a character or binary column.
`cursortype[=intval]`
  Sets or queries the cursor type used for fetches.
`noscan[=bool]`
  Sets or queries whether the driver scans SQL strings for ODBC escape clauses.
`rowsetsize`
  Returns the number of rows in a rowset fetched internally by a call to SQLExtendedFetch (hardcoded to 1).
`nparams`
  Returns the number of parameters of the statement.
`parameter(n)`
  Returns information of the n-th parameter of the query as ODBC::Parameter.
`parameters`
  Returns an array of ODBC::Parameters describing all parameters of the query.
`param_type(n[,type,coldef,scale])`
  Allows to override the type of parameter n and returns the current type. This can be useful when the ODBC driver does not provide proper type information on SQLDescribeParam.
`param_iotype(n[,iotype])`
  Allows to change the input/output type of parameter n and returns the current input/output type. By default, all parameters are ODBC::SQL_PARAM_INPUT. When calling a stored procedure in the statement, the output parameter must be altered using this method, e.g.

      # assume 1st parameter is input, 2nd is output
      stmt = conn.prepare("call stored_proc( ?, ?)")
      # setup 2nd for output of an integer
      stmt.param_iotype(2, ODBC::SQL_PARAM_OUTPUT)
      stmt.param_output_type(2, ODBC::SQL_INTEGER)
      stmt.param_output_size(2, 4)
      # execute stmt and retrieve value of output parameter
      stmt.execute(42, nil)
      stmt.fetch_all
      out_value = stmt.param_output_value(2);

`param_output_type(n[,type])`
  Allows to change the SQL type of output parameter n and returns the current type. For further information see the sample code in the `param_iotype` method.
`param_output_size(n[,size])`
  Allows to change the byte size of the buffer for output parameter n and returns the current size. For further information see the sample code in the `param_iotype` method.
`param_output_value(n)`
  Returns the value of the output parameter n. For further information see the sample code in the `param_iotype` method.
`make_proc([n])`
  Wraps the statement into a ODBCProc object and returns that object. The optional n argument is the parameter number of the statement which is used as output parameter in the wrapped ODBCProc. For further information refer to the samples in the description of `ODBC::Database.proc`.

### singleton methods:

`make_proc(stmt,[n])`
  Wraps the statement stmt into a ODBCProc object and returns that object. The optional n argument is the parameter number of the statement which is used as output parameter in the wrapped ODBCProc. For further information refer to the samples in the description of `ODBC::Database.proc`.

### Remarks:

The `fetch`, `fetch_hash`, and `execute` methods can be invoked with a block. In this case the block is executed with one row of the result set (`fetch` and `fetch_hash`) or with the ODBC::Statement (`execute`) as parameter.

If the `ignorecase` option is turned on, all column names used in the `column`, `columns`, and `*_hash` methods are converted to upper case.

## ODBC::Column

The class to represent (read-only) information of a column of a query. Objects of this class are created as result of the `column` and `columns` methods of ODBC::Statement.

### super class:

`ODBC::Object`

### methods:

`name`
  Returns the column name (String).
`table`
  Returns the table name (String).
`length`
  Returns the length of the column (Integer).
`nullable`
  Returns the nullable state of the column (Boolean).
`searchable`
  Returns the searchable state of the column (Boolean).
`unsigned`
  Returns the unsigned flag of the column (Boolean).
`precision`
  Returns the precision of the column (Integer).
`scale`
  Returns the scale of the column (Integer).
`type`
  Returns the SQL type of the column (Integer).
`autoincrement`
  Returns true if the column automatically increments, false, if not, and nil if that information cannot be determined from the column.

## ODBC::Parameter

The class to represent (read-only) information of a parameter of a query. Objects of this class are created as result of the `parameter` and `parameters` methods of ODBC::Statement.

### super class:

`ODBC::Object`

### methods:

`type`
  Returns the parameter's type, e.g. ODBC::SQL_CHAR.
`precision`
  Returns the parameter's precision (Integer).
`length`
  Returns the parameter's scale (Integer).
`nullable`
  Returns the nullable state of the column (Boolean).
`iotype`
  Returns the parameter's input/output type, e.g. ODBC::SQL_PARAM_INPUT.
`output_type`
  Returns the parameter's output type, only useful when the parameter is an output parameter (ODBC::SQL_PARAM_OUTPUT or ODBC::SQL_PARAM_INPUT_OUTPUT).
`output_size`
  Returns the parameter's output buffer size, only useful when the parameter is an output parameter (ODBC::SQL_PARAM_OUTPUT).

## ODBC::Date

The class to represent a `SQL_DATE` column in a table or a `SQL_DATE` query parameter.

### super class:

`ODBC::Object`

### mixins:

`Comparable`

### methods:

`<=>(adate)`
  Comparison, compares date with adate and returns 0, 1, or -1.
`day[=num]`
  Returns or sets the day component of the date object.
`month[=num]`
  Returns or sets the month component of the date object.
`year[=num]`
  Returns or sets the year component of the date object.
`to_s`
  Returns a string representation of the object with format `YYYY-MM-DD`.
`clone`
  Returns a fresh copy of the date object.

### singleton methods:

`new([year, month, day])`
`new(date)`
`new(time)`
`new(string)`
  Creates a new date object from numeric values or from a `Date`, `Time`, or `String` object. Recognized string formats are e.g.

      2001-01-01
      2001-01-01 12:00:01
      {ts '2001-01-01 12:00:01.1'}
      {d '2001-01-01'}

## ODBC::Time

The class to represent a `SQL_TIME` column in a table or a `SQL_TIME` query parameter.

### super class:

`ODBC::Object`

### mixins:

`Comparable`

### methods:

`<=>(atime)`
  Comparison, compares time with atime and returns 0, 1, or -1.
`second[=num]`
  Returns or sets the second component of the time object.
`minute[=num]`
  Returns or sets the minute component of the time object.
`hour[=num]`
  Returns or sets the hour component of the time object.
`to_s`
  Returns a string representation of the object with format `hh:mm:ss`.
`clone`
  Returns a fresh copy of the time object.

### singleton methods:

`new([hour, minute, second])`
`new(time)`
`new(string)`
  Creates a new time object from numeric values or from a `Time` or `String` object. Recognized string formats are e.g.

      12:00:01
      2001-01-01 12:00:01
      {ts '2001-01-01 12:00:01.1'}
      {t '12:00:01'}

## ODBC::TimeStamp

The class to represent a `SQL_TIMESTAMP` column in a table or a `SQL_TIMESTAMP` query parameter.

### super class:

`ODBC::Object`

### mixins:

`Comparable`

### methods:

`<=>(atimestamp)`
  Comparison, compares time stamp with atimestamp and returns 0, 1, or -1.
`fraction[=num]`
  Returns or sets the fraction component of the time stamp object. Note that this is expressed in nanoseconds.
`second[=num]`
  Returns or sets the second component of the time stamp object.
`minute[=num]`
  Returns or sets the minute component of the time stamp object.
`hour[=num]`
  Returns or sets the hour component of the time stamp object.
`day[=num]`
  Returns or sets the day component of the time stamp object.
`month[=num]`
  Returns or sets the month component of the time stamp object.
`year[=num]`
  Returns or sets the year component of the time stamp object.
`to_s`
  Returns a string representation of the object with format `YYYY-MM-DD hh:mm:ss fraction`.
`clone`
  Returns a fresh copy of the time stamp object.

### singleton methods:

`new([year, month, day, hour, minute, second, fraction])`
`new(time)`
`new(string)`
  Creates a new time stamp object from numeric values or from a `Time` or `String` object. Recognized string formats are e.g.

      12:00:01
      2001-01-01
      2001-01-01 12:00:01
      {ts '2001-01-01 12:00:01.1'}
      {d '2001-01-01'}
      {t '12:00:01'}

## ODBC::DSN

The class to represent a data source name. Objects of this class are created as result of a `ODBC::datasources` module function call.

### super class:

`ODBC::Object`

### methods:

`name[=name]`
  Queries or sets the name (String) of the data source.
`descr[=descr]`
  Queries or sets the descr (description, String) of the data source.

### singleton methods:

`new`
  Returns an empty ODBC::DSN object.

## ODBC::Driver

The class to represent an ODBC driver with name and attributes. Objects of this class are created as result of a `ODBC::drivers` module function call.

### super class:

`ODBC::Object`

### methods:

`name[=name]`
  Queries or sets the name (String) of the ODBC driver.
`attrs[[key][=value]]`
  Queries or sets attributes in the attrs Hash of the ODBC driver object. The keys and values should be Strings.

### singleton methods:

`new`
  Returns an empty ODBC::Driver object.

## ODBCProc

The class to represent a procedure with ODBC database/statement context. Objects of this class are created as result of a `ODBC::Database.proc` method call.

### super class:

`Proc`

### methods:

`call([args*])`
  Executes the SQL statement with parameters set from args and then invokes the procedure's block, setting the block's single parameter to the ODBC::Statement.
`[[args*]]`
  Synonym for `call`.

## ODBC::Error

The class to represent ODBC related exceptions. The descriptive string is made up of the first ODBC driver or driver manager message as concatenation of SQL state, native error, driver manager name, database name/vendor, DSN, and error text, e.g.

    S1000 (1146) [unixODBC][TCX][MySQL]Table 'test.foo' doesn't exist

For internally generated errors, e.g. method invocation on a broken connection, the descriptive string starts with 'INTERN' and native error 0, e.g.

    INTERN (0) [RubyODBC]No connection

For errors programmatically generated by the `raise` method, the descriptive string starts with 'INTERN' and native error 1, e.g.

    INTERN (1) [RubyODBC]Programmer forgot to RTFM

### super class:

`StandardError`

## Undocumented

### Use The Source, Luke!

`ODBC::add_dsn(driver,issys=false)`
`ODBC::add_dsn(name,attrs,issys=false)`
`ODBC::config_dsn(driver,issys=false)`
`ODBC::config_dsn(name,attrs,issys=false)`
`ODBC::del_dsn(driver,issys=false)`
`ODBC::del_dsn(name,attrs,issys=false)`
`ODBC::write_file_dsn(filename,appname,key[,value])`
`ODBC::read_file_dsn(filename,appname,key)`
`ODBC::trace([mask])`
`ODBC::Statement.fetch!`
`ODBC::Statement.fetch_first!`
`ODBC::Statement.fetch_first_hash(with_table_names=false,use_sym=false)`
`ODBC::Statement.fetch_scroll!(direction,offset=1)`
`ODBC::Statement.fetch_hash!(with_table_names=false,use_sym=false)`