# ij commands and errors reference

This section describes the commands and errors within the `ij` tool.

- ij commands
  ij accepts several commands to control its use of JDBC.
- Absolute command
  The Absolute command moves the cursor to the row specified by the int argument, then fetches the row.
- After Last command
  The After Last command moves the cursor to after the last row, then fetches the row.
- Async command
  The Async command lets you execute an SQL statement in a separate thread.
- Autocommit command
  The Autocommit command turns the connection's auto-commit mode on or off.
- Before First command
  The Before First command moves the cursor to before the first row, then fetches the row.
- Close command
  The Close command closes the named cursor.
- Commit command
  The Commit command issues a java.sql.Connection.commit request.
- Connect command
  The Connect command connects to the database indicated by the ConnectionURLString argument.
- Describe command
  The Describe command provides a decription of the specified table or view.
- Disconnect command
  The Disconnect command disconnects from the database.
- Driver command
  The Driver command takes the value of the DriverNameString argument and issues a Class.forName request to load the named class.
- Elapsedtime command
  The Elapsedtime command, if set to ON, displays the total time elapsed during statement execution.
- Execute command
  The Execute command executes an SQL statement or a named prepared statement.
- Exit command
  The Exit command causes the ij application to complete and processing to halt.
- First command
  The First command moves the cursor to the first row in the ResultSet, then fetches the row.
- Get Cursor command
  The Get Cursor command creates a cursor with the name of the specified Identifier by issuing a java.sql.Statement.executeQuery request on the value of the specified String.
- Get Scroll Insensitive Cursor command
  The Get Scroll Insensitive Cursor command creates a scrollable insensitive cursor with the name of the specified Identifier.
- Help command
  The Help command prints out a brief list of the ij commands.
- HoldForConnection command
  The HoldForConnection command sets the default holdability for a connection to the default ResultSet.HOLD_CURSORS_OVER_COMMIT.
- Last command
  The Last command moves the cursor to the last row in the ResultSet, then fetches the row.
- LocalizedDisplay command
  The LocalizedDisplay command specifies that ij should display locale-sensitive data (such as dates) in the native format for the ij locale.
- MaximumDisplayWidth command
  The MaximumDisplayWidth command sets the largest display width for columns to the specified value.
- Next command
  The Next command fetches the next row from the specified named cursor.
- NoHoldForConnection command
  The NoHoldForConnection command changes the default holdability for a connection from ResultSet.HOLD_CURSORS_OVER_COMMIT to ResultSet.CLOSE_CURSORS_AT_COMMIT.
- Prepare command
  The Prepare command creates a java.sql.PreparedStatement using the value of the specified String, accessible in ij by the Identifier given to it.
- Previous command
  The Previous command moves the cursor to the row previous to the current one, then fetches the row.
- Protocol command
  The Protocol command specifies the protocol for establishing connections and automatically loads the appropriate driver.
- Readonly command
  The Readonly command sets the current connection to a "read-only" connection, as if the current user were defined as a readOnlyAccess user.
- Relative command
  The Relative command moves the cursor to the row that is the specified number of rows relative to the current row, then fetches the row.
- Remove command
  The Remove command removes a previously prepared statement from ij.
- Rollback command
  The Rollback command issues a java.sql.Connection.rollback request.
- Run command
  The Run command redirects ij processing to read from a specified file.
- Set Connection command
  The Set Connection command specifies which connection to make current when more than one connection is open.
- Show command
  The Show command displays information about active connections and database objects.
- Wait For command
  The Wait For command displays the results of a previously started asynchronous command.
- Syntax for comments in ij commands
  ij accepts two forms of comments in commands.
- Syntax for identifiers in ij commands
  Some ij commands require identifier arguments.
- Syntax for strings in ij commands
  Some ij commands require string arguments.
- ij errors
  ij might issue messages to inform the user of errors during processing of statements.