Impala Shell Command Reference

Use the following commands within impala-shell to pass requests to the impalad daemon that the shell is connected to. You can enter a command interactively at the prompt or pass it as the argument to the -q option of impala-shell.


Command	Explanation
Impala SQL statements	You can issue valid SQL statements to be executed.
`connect`	Connects to the specified instance of `impalad`. The default port of 21000 is assumed unless you provide another value. You can connect to any host in your cluster that is running `impalad`. If you connect to an instance of `impalad` that was started with an alternate port specified by the `--fe_port` flag, you must provide that alternate port.
`help`	Help provides a list of all available commands and options.
`history`	Maintains an enumerated cross-session command history. This history is stored in the ~/.impalahistory file.
`profile`	Displays low-level information about the most recent query. Used for performance diagnosis and tuning. The report starts with the same information as produced by the `EXPLAIN` statement and the `SUMMARY` command.
`quit`	Exits the shell. Remember to include the final semicolon so that the shell recognizes the end of the command.
`rerun` or `@`	Executes a previous impala-shell command again, from the list of commands displayed by the `history` command. These could be SQL statements, or commands specific to impala-shell such as `quit` or `profile`. Specify an integer argument. A positive integer `N` represents the command labelled `N` in the output of the `HISTORY` command. A negative integer `-N` represents the `N`th command from the end of the list, such as -1 for the most recent command. Commands that are executed again do not produce new entries in the `HISTORY` output list.
`set`	Manages query options for an impala-shell session. These options are used for query tuning and troubleshooting. Issue `SET` with no arguments to see the current query options, either based on the impalad defaults, as specified by you at impalad startup, or based on earlier `SET` statements in the same session. To modify option values, issue commands with the syntax `set option=value`. To restore an option to its default, use the `unset` command.
`shell`	Executes the specified command in the operating system shell without exiting `impala-shell`. You can use the `!` character as shorthand for the `shell` command. note Quote any instances of the `--` or `/*` tokens to avoid them being interpreted as the start of a comment. To embed comments within `source` or `!` commands, use the shell comment character `#` before the comment portion of the line.
`source` or `src`	Executes one or more statements residing in a specified file from the local filesystem. Allows you to perform the same kinds of batch operations as with the `-f` option, but interactively within the interpreter. The file can contain SQL statements and other impala-shell commands, including additional `SOURCE` commands to perform a flexible sequence of actions. Each command or statement, except the last one in the file, must end with a semicolon.
`summary`	Summarizes the work performed in various stages of a query. It provides a higher-level view of the information displayed by the `EXPLAIN` command. Added in Impala 1.4.0. The time, memory usage, and so on reported by `SUMMARY` only include the portions of the statement that read data, not when data is written. Therefore, the `PROFILE` command is better for checking the performance and scalability of `INSERT` statements. You can see a continuously updated report of the summary information while a query is in progress.
`unset`	Removes any user-specified value for a query option and returns the option to its default value. You can also use it to remove user-specified substitution variables using the notation `UNSET VAR:variable_name`.
`use`	Indicates the database against which to execute subsequent commands. Lets you avoid using fully qualified names when referring to tables in databases other than `default`. Not effective with the `-q` option, because that option only allows a single statement in the argument.
`version`	Returns Impala version information.