cockroach sql

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CockroachDB comes with a built-in client for executing SQL statements from an interactive shell or directly from the command line. To use this client, run the cockroach sql command as described below.

To exit the interactive shell, use \q, quit, exit, or ctrl-d.

Tip:

If you want to experiment with CockroachDB SQL but do not have a cluster already running, you can use the cockroach demo command to open a shell to a temporary, in-memory cluster.

Synopsis

Start the interactive SQL shell:

$ cockroach sql <flags>

Execute SQL from the command line:

$ cockroach sql --execute="<sql statement>;<sql statement>" --execute="<sql-statement>" <flags>

$ echo "<sql statement>;<sql statement>" | cockroach sql <flags>

$ cockroach sql <flags> < file-containing-statements.sql

Exit the interactive SQL shell:

$ \q

$ quit

$ exit

ctrl-d

View help:

$ cockroach sql --help

Flags

The sql command supports the following types of flags:

General Use
Client Connection
Logging

General

To start an interactive SQL shell, run cockroach sql with all appropriate connection flags or use just the --url flag, which includes connection details.
To execute SQL statements from the command line, use the --execute flag.

Flag	Description
`--database` `-d`	A database name to use as current database in the newly created session.
`--echo-sql`	Reveal the SQL statements sent implicitly by the command-line utility. For a demonstration, see the example below. This can also be enabled within the interactive SQL shell via the `\set echo` shell command.
`--execute` `-e`	Execute SQL statements directly from the command line, without opening a shell. This flag can be set multiple times, and each instance can contain one or more statements separated by semi-colons. If an error occurs in any statement, the command exits with a non-zero status code and further statements are not executed. The results of each statement are printed to the standard output (see `--format` for formatting options). For a demonstration of this and other ways to execute SQL from the command line, see the example below.
`--format`	How to display table rows printed to the standard output. Possible values: `tsv`, `csv`, `table`, `raw`, `records`, `sql`, `html`. Default: `table` for sessions that output on a terminal; `tsv` otherwise This flag corresponds to the `display_format` client-side option.
`--safe-updates`	Disallow potentially unsafe SQL statements, including `DELETE` without a `WHERE` clause, `UPDATE` without a `WHERE` clause, and `ALTER TABLE ... DROP COLUMN`. Default: `true` for interactive sessions; `false` otherwise Potentially unsafe SQL statements can also be allowed/disallowed for an entire session via the `sql_safe_updates` session variable.
`--set`	Set a client-side option before starting the SQL shell or executing SQL statements from the command line via `--execute`. This flag may be specified multiple times, once per option. After starting the SQL shell, the `\set` and `unset` commands can be use to enable and disable client-side options as well.
`--watch`	Repeat the SQL statements specified with `--execute` or `-e` until a SQL error occurs or the process is terminated. `--watch` applies to all `--execute` or `-e` flags in use. You must also specify an interval at which to repeat the statement, followed by a time unit. For example, to specify an interval of 5 seconds, use `5s`. Note that this flag is intended for simple monitoring scenarios during development and testing. See the example below.

Client connection

Flag	Description
`--host`	The server host and port number to connect to. This can be the address of any node in the cluster. Env Variable: `COCKROACH_HOST` Default: `localhost:26257`
`--port` `-p`	The server port to connect to. Note: The port number can also be specified via `--host`. Env Variable: `COCKROACH_PORT` Default: `26257`
`--user` `-u`	The SQL user that will own the client session. Env Variable: `COCKROACH_USER` Default: `root`
`--insecure`	Use an insecure connection. Env Variable: `COCKROACH_INSECURE` Default: `false`
`--certs-dir`	The path to the certificate directory containing the CA and client certificates and client key. Env Variable: `COCKROACH_CERTS_DIR` Default: `${HOME}/.cockroach-certs/`
`--url`	A connection URL to use instead of the other arguments. Env Variable: `COCKROACH_URL` Default: no URL

See Client Connection Parameters for more details.

Logging

By default, the sql command logs errors to stderr.

If you need to troubleshoot this command's behavior, you can change its logging behavior.

Session and output types

cockroach sql exhibits different behaviors depending on whether or not the session is interactive and/or whether or not the session outputs on a terminal.

A session is interactive when cockroach sql is invoked without the --execute flag and input is not redirected from a file. In such cases:
- The errexit option defaults to false.
- The check_syntax option defaults to true if supported by the CockroachDB server (this is checked when the shell starts up).
- Ctrl+C at the prompt will only terminate the shell if no other input was entered on the same line already.
- The shell will attempt to set the safe_updates session variable to true on the server.
A session outputs on a terminal when output is not redirected to a file. In such cases:
- The --format flag and its corresponding display_format option default to table. These default to tsv otherwise.
- The show_times option defaults to true.

When a session is both interactive and outputs on a terminal, cockroach sql also activates the interactive prompt with a line editor that can be used to modify the current line of input. Also, command history becomes active.

SQL shell

Welcome message

When the SQL shell connects (or reconnects) to a CockroachDB node, it prints a welcome text with some tips and CockroachDB version and cluster details:

#
# Welcome to the CockroachDB SQL shell.
# All statements must be terminated by a semicolon.
# To exit, type: \q.
#
# Server version: CockroachDB CCL v20.1.17 (x86_64-apple-darwin17.7.0, built 2019/09/13 00:07:19, go1.12.6) (same version as client)
# Cluster ID: 7fb9f5b4-a801-4851-92e9-c0db292d03f1
#
# Enter \? for a brief introduction.
#
>

The Version and Cluster ID details are particularly noteworthy:

When the client and server versions of CockroachDB are the same, the shell prints the Server version followed by (same version as client).
When the client and server versions are different, the shell prints both the Client version and Server version. In this case, you may want to plan an upgrade of older client or server versions.
Since every CockroachDB cluster has a unique ID, you can use the Cluster ID field to verify that your client is always connecting to the correct cluster.

Commands

The following commands can be used within the interactive SQL shell:

Command	Usage
`\?` `help`	View this help within the shell.
`\q` `quit` `exit` `ctrl-d`	Exit the shell. When no text follows the prompt, `ctrl-c` exits the shell as well; otherwise, `ctrl-c` clears the line.
`\!`	Run an external command and print its results to `stdout`. See the example below.
`\\|`	Run the output of an external command as SQL statements. See the example below.
`\set <option>` `\unset <option>`	Enable or disable a client-side option. For more details, see Client-side options. You can also use the `--set` flag to enable or disable client-side options before starting the SQL shell.
`\show`	During a multi-line statement or transaction, show the SQL entered so far.
`\h <statement>` `\hf <function>`	View help for specific SQL statements or functions. See SQL shell help for more details.
`\l`	List all databases in the CockroachDB cluster. This command is equivalent to `SHOW DATABASES`.
`\dt` `d`	Show the tables of the current schema in the current database. These commands are equivalent to `SHOW TABLES`.
`\du`	List the users for all databases. This command is equivalent to `SHOW USERS`.
`\d <table>`	Show details about columns in the specified table. This command is equivalent to `SHOW COLUMNS`.

Client-side options

To view option descriptions and how they are currently set, use \set without any options.
To enable or disable an option, use \set <option> <value> or \unset <option> <value>. You can also use the form <option>=<value>.
If an option accepts a boolean value:
- \set <option> without <value> is equivalent to \set <option> true, and \unset <option> without <value> is equivalent to \set <option> false.
- on and 0 are aliases for true, and off and 1 are aliases for false.

Client Options	Description
`auto_trace`	For every statement executed, the shell also produces the trace for that statement in a separate result below. A trace is also produced in case the statement produces a SQL error. Default: `off` To enable this option, run `\set auto_trace on`.
`display_format`	How to display table rows printed within the interactive SQL shell. Possible values: `tsv`, `csv`, `table`, `raw`, `records`, `sql`, `html`. Default: `table` for sessions that output on a terminal; `tsv` otherwise To change this option, run `\set display_format <format>`. For a demonstration, see the example below.
`echo`	Reveal the SQL statements sent implicitly by the SQL shell. Default: `false` To enable this option, run `\set echo`. For a demonstration, see the example below.
`errexit`	Exit the SQL shell upon encountering an error. Default: `false` for interactive sessions; `true` otherwise To enable this option, run `\set errexit`.
`check_syntax`	Validate SQL syntax. This ensures that a typo or mistake during user entry does not inconveniently abort an ongoing transaction previously started from the interactive shell. Default: `true` for interactive sessions; `false` otherwise. To disable this option, run `\unset check_syntax`.
`show_times`	Reveal the time a query takes to complete. Default: `true` To disable this option, run `\unset show_times`.
`smart_prompt`	Query the server for the current transaction status and return it to the prompt. Note that this option is respected only when `ECHO` is enabled as well. Default: `true` for interactive sessions; `false` otherwise To disable this option, run `\unset smart_prompt`.

Help

Within the SQL shell, you can get interactive help about statements and functions:

Command	Usage
`\h` `??`	List all available SQL statements, by category.
`\hf`	List all available SQL functions, in alphabetical order.
`\h <statement>` or `<statement> ?`	View help for a specific SQL statement.
`\hf <function>` or `<function> ?`	View help for a specific SQL function.

Examples

> \h UPDATE

Command:     UPDATE
Description: update rows of a table
Category:    data manipulation
Syntax:
UPDATE <tablename> [[AS] <name>] SET ... [WHERE <expr>] [RETURNING <exprs...>]

See also:
  SHOW TABLES
  INSERT
  UPSERT
  DELETE
  https://www.cockroachlabs.com/docs/v2.1/update.html

> \hf uuid_v4

Function:    uuid_v4
Category:    built-in functions
Returns a UUID.

Signature          Category
uuid_v4() -> bytes [ID Generation]

See also:
  https://www.cockroachlabs.com/docs/v2.1/functions-and-operators.html

Shortcuts

The SQL shell supports many shortcuts, such as ctrl-r for searching the shell history. For full details, see this Readline Shortcut reference.

Error messages and `SQLSTATE` codes

When CockroachDB encounters a SQL error, it returns the following information to the client (whether cockroach sql or another client application):

An error message, prefixed with the "Severity" field of the PostgreSQL wire protocol. For example, ERROR: insert on table "shipments" violates foreign key constraint "fk_customers".
A 5-digit SQLSTATE error code as defined by the SQL standard. For example, SQLSTATE: 23503.

For example, the following query (taken from this example of adding multiple foreign key constraints) results in a SQL error, and returns both an error message and a SQLSTATE code as described above.

> INSERT INTO shipments (carrier, status, customer_id) VALUES ('DHL', 'At facility', 2000);

ERROR: insert on table "shipments" violates foreign key constraint "fk_customers"
SQLSTATE: 23503
DETAIL: Key (customer_id)=(2000) is not present in table "customers".

The SQLSTATE code in particular can be helpful in the following ways:

It is a standard SQL error code that you can look up in documentation and search for on the web. For any given error state, CockroachDB tries to produce the same SQLSTATE code as PostgreSQL.
If you are developing automation that uses the CockroachDB SQL shell, it is more reliable to check for SQLSTATE values than for error message strings, which are likely to change.

Examples

Start a SQL shell

In these examples, we connect a SQL shell to a secure cluster.

# Using standard connection flags:
$ cockroach sql \
--certs-dir=certs \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb

# Using the --url flag:
$ cockroach sql \
--url="postgresql://maxroach@12.345.67.89:26257/critterdb?sslcert=certs/client.maxroach.crt&sslkey=certs/client.maxroach.key&sslmode=verify-full&sslrootcert=certs/ca.crt"

In these examples, we connect a SQL shell to an insecure cluster.

# Using standard connection flags:
$ cockroach sql --insecure \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb

# Using the --url flag:
$ cockroach sql \
--url="postgresql://maxroach@12.345.67.89:26257/critterdb?sslmode=disable"

Execute SQL statement within the SQL shell

This example assume that we have already started the SQL shell (see examples above).

> CREATE TABLE animals (id INT PRIMARY KEY DEFAULT unique_rowid(), name STRING);

> INSERT INTO animals (name) VALUES ('bobcat'), ('🐢 '), ('barn owl');

> SELECT * FROM animals;

+--------------------+----------+
|         id         |   name   |
+--------------------+----------+
| 148899952591994881 | bobcat   |
| 148899952592060417 | 🐢        |
| 148899952592093185 | barn owl |
+--------------------+----------+

Execute SQL statements from the command line

In these examples, we use the --execute flag to execute statements from the command line:

# Statements with a single --execute flag:
$ cockroach sql --insecure \
--execute="CREATE TABLE roaches (name STRING, country STRING); INSERT INTO roaches VALUES ('American Cockroach', 'United States'), ('Brownbanded Cockroach', 'United States')" \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb

CREATE TABLE
INSERT 2

# Statements with multiple --execute flags:
$ cockroach sql --insecure \
--execute="CREATE TABLE roaches (name STRING, country STRING)" \
--execute="INSERT INTO roaches VALUES ('American Cockroach', 'United States'), ('Brownbanded Cockroach', 'United States')" \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb

CREATE TABLE
INSERT 2

In this example, we use the echo command to execute statements from the command line:

# Statements with the echo command:
$ echo "SHOW TABLES; SELECT * FROM roaches;" | cockroach sql --insecure --user=maxroach --host=12.345.67.89 --database=critterdb

+----------+
|  Table   |
+----------+
| roaches  |
+----------+
+-----------------------+---------------+
|         name          |    country    |
+-----------------------+---------------+
| American Cockroach    | United States |
| Brownbanded Cockroach | United States |
+-----------------------+---------------+

Control how table rows are printed

In these examples, we show tables and special characters printed in various formats.

When the standard output is a terminal, --format defaults to table and tables are printed with ASCII art and special characters are not escaped for easy human consumption:

$ cockroach sql --insecure \
--execute="SELECT '🐥' AS chick, '🐢' AS turtle" \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb

+-------+--------+
| chick | turtle |
+-------+--------+
| 🐥    | 🐢     |
+-------+--------+

However, you can explicitly set --format to another format, for example, tsv or html:

$ cockroach sql --insecure \
--format=tsv \
--execute="SELECT '🐥' AS chick, '🐢' AS turtle" \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb

1 row
chick   turtle
🐥    🐢

$ cockroach sql --insecure \
--format=html \
--execute="SELECT '🐥' AS chick, '🐢' AS turtle" \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb

<table>
<thead><tr><th>chick</th><th>turtle</th></tr></head>
<tbody>
<tr><td>🐥</td><td>🐢</td></tr>
</tbody>
</table>

When piping output to another command or a file, --format defaults to tsv:

$ cockroach sql --insecure \
--execute="SELECT '🐥' AS chick, '🐢' AS turtle" > out.txt \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb

$ cat out.txt

1 row
chick   turtle
🐥    🐢

However, you can explicitly set --format to another format, for example, table:

$ cockroach sql --insecure \
--format=table \
--execute="SELECT '🐥' AS chick, '🐢' AS turtle" > out.txt \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb

$ cat out.txt

+-------+--------+
| chick | turtle |
+-------+--------+
| 🐥    | 🐢     |
+-------+--------+
(1 row)

Make the output of `SHOW` statements selectable

To make it possible to select from the output of SHOW statements, set --format to raw:

$ cockroach sql --insecure \
--format=raw \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb

> SHOW CREATE customers;

# 2 columns
# row 1
## 14
test.customers
## 185
CREATE TABLE customers (
    id INT NOT NULL,
    email STRING NULL,
    CONSTRAINT "primary" PRIMARY KEY (id ASC),
    UNIQUE INDEX customers_email_key (email ASC),
    FAMILY "primary" (id, email)
)
# 1 row

When --format is not set to raw, you can use the display_format SQL shell option to change the output format within the interactive session:

> \set display_format raw

# 2 columns
# row 1
## 14
test.customers
## 185
CREATE TABLE customers (
  id INT NOT NULL,
  email STRING NULL,
  CONSTRAINT "primary" PRIMARY KEY (id ASC),
  UNIQUE INDEX customers_email_key (email ASC),
  FAMILY "primary" (id, email)
)
# 1 row

Execute SQL statements from a file

In this example, we show and then execute the contents of a file containing SQL statements.

$ cat statements.sql

CREATE TABLE roaches (name STRING, country STRING);
INSERT INTO roaches VALUES ('American Cockroach', 'United States'), ('Brownbanded Cockroach', 'United States');

$ cockroach sql --insecure \
--user=maxroach \
--host=12.345.67.89 \
--database=critterdb \
< statements.sql

CREATE TABLE
INSERT 2

Run external commands from the SQL shell

In this example, we use \! to look at the rows in a CSV file before creating a table and then using \| to insert those rows into the table.

Note:

This example works only if the values in the CSV file are numbers. For values in other formats, use an online CSV-to-SQL converter or make your own import program.

> \! cat test.csv

12, 13, 14
10, 20, 30

> CREATE TABLE csv (x INT, y INT, z INT);

> \| IFS=","; while read a b c; do echo "insert into csv values ($a, $b, $c);"; done < test.csv;

> SELECT * FROM csv;

+----+----+----+
| x  | y  | z  |
+----+----+----+
| 12 | 13 | 14 |
| 10 | 20 | 30 |
+----+----+----+

In this example, we create a table and then use \| to programmatically insert values.

> CREATE TABLE for_loop (x INT);

> \| for ((i=0;i<10;++i)); do echo "INSERT INTO for_loop VALUES ($i);"; done

> SELECT * FROM for_loop;

+---+
| x |
+---+
| 0 |
| 1 |
| 2 |
| 3 |
| 4 |
| 5 |
| 6 |
| 7 |
| 8 |
| 9 |
+---+

Edit SQL statements in an external editor

In applications that use GNU Readline (such as bash), you can edit a long line in your preferred editor by typing Ctrl-x Ctrl-e. However, CockroachDB uses the BSD-licensed libedit, which does not include this functionality.

If you would like to be able to edit the current line in an external editor by typing C-x C-e as in bash, do the following:

Install the vipe program (from the moreutils suite of tools).
Edit your ~/.editrc to add the following line, which takes advantage of the SQL client's ability to run external commands:
```
cockroach:bind -s ^X^E '^A^K\\\| echo \"^Y\" | vipe\r'
```

This tells libedit to translate C-x C-e into the following commands:

Move to the beginning of the current line.
Cut the whole line.
Paste the line into your editor via vipe.
Pass the edited file back to the SQL client when vipe exits.

Note:

Future versions of the SQL client may opt to use a different back-end for reading input, in which case please refer to this page for additional updates.

Allow potentially unsafe SQL statements

The --safe-updates flag defaults to true. This prevents SQL statements that may have broad, undesired side-effects. For example, by default, we cannot use DELETE without a WHERE clause to delete all rows from a table:

$ cockroach sql --insecure --execute="SELECT * FROM db1.t1"

+----+------+
| id | name |
+----+------+
|  1 | a    |
|  2 | b    |
|  3 | c    |
|  4 | d    |
|  5 | e    |
|  6 | f    |
|  7 | g    |
|  8 | h    |
|  9 | i    |
| 10 | j    |
+----+------+
(10 rows)

$ cockroach sql --insecure --execute="DELETE FROM db1.t1"

Error: pq: rejected: DELETE without WHERE clause (sql_safe_updates = true)
Failed running "sql"

However, to allow an "unsafe" statement, you can set --safe-updates=false:

$ cockroach sql --insecure --safe-updates=false --execute="DELETE FROM db1.t1"

DELETE 10

Note:

Potentially unsafe SQL statements can also be allowed/disallowed for an entire session via the sql_safe_updates session variable.

Reveal the SQL statements sent implicitly by the command-line utility

In this example, we use the --execute flag to execute statements from the command line and the --echo-sql flag to reveal SQL statements sent implicitly:

$ cockroach sql --insecure \
--execute="CREATE TABLE t1 (id INT PRIMARY KEY, name STRING)" \
--execute="INSERT INTO t1 VALUES (1, 'a'), (2, 'b'), (3, 'c')" \
--user=maxroach \
--host=12.345.67.89 \
--database=db1
--echo-sql

# Server version: CockroachDB CCL f8f3c9317 (darwin amd64, built 2017/09/13 15:05:35, go1.8) (same version as client)
# Cluster ID: 847a4ba5-c78a-465a-b1a0-59fae3aab520
> SET sql_safe_updates = TRUE
> CREATE TABLE t1 (id INT PRIMARY KEY, name STRING)
CREATE TABLE
> INSERT INTO t1 VALUES (1, 'a'), (2, 'b'), (3, 'c')
INSERT 3

In this example, we start the interactive SQL shell and enable the echo shell option to reveal SQL statements sent implicitly:

$ cockroach sql --insecure \
--user=maxroach \
--host=12.345.67.89 \
--database=db1

> \set echo

> INSERT INTO db1.t1 VALUES (4, 'd'), (5, 'e'), (6, 'f');

> INSERT INTO db1.t1 VALUES (4, 'd'), (5, 'e'), (6, 'f');
INSERT 3

Time: 2.426534ms

> SHOW TRANSACTION STATUS
> SHOW DATABASE

Repeat a SQL statement

Repeating SQL queries on a table can be useful for monitoring purposes. With the --watch flag, you can repeat the statements specified with a --execute or -e flag periodically, until a SQL error occurs or the process is terminated.

For example, if you want to monitor the number of queries running on the current node, you can use cockroach sql with the --watch flag to query the node's crdb_internal.node_statement_statistics table for the query count:

$ cockroach sql --insecure \
--execute="SELECT SUM(count) FROM crdb_internal.node_statement_statistics" \
--watch 1m

  sum
+-----+
  926
(1 row)
  sum
+------+
  4227
(1 row)
^C

In this example, the statement is executed every minute. We let the process run for a couple minutes before stopping it with Ctrl+C.

Connect to a cluster listening for Unix domain socket connections

New in v20.1: To connect to a cluster that is running on the same machine as your client and is listening for Unix domain socket connections, specify a Unix domain socket URI with the --url connection parameter.

For example, suppose you start a single-node cluster with the following cockroach start-single-node command:

$ cockroach start-single-node --insecure --socket-dir=/tmp

CockroachDB node starting at 2020-04-22 15:07:17.232326 +0000 UTC (took 0.9s)
build:               CCL v20.1.0 @ 2020/04/22 13:54:06 (go1.13.4)
webui:               http://localhost:8080
sql:                 postgresql://root@localhost:26257?sslmode=disable
RPC client flags:    ./cockroach <client cmd> --host=localhost:26257 --insecure
socket:              /tmp/.s.PGSQL.26257
logs:                /path/cockroach/cockroach-data/logs
temp dir:            /path/cockroach/cockroach-data/cockroach-temp919020614
external I/O path:   /path/cockroach/cockroach-data/extern
store[0]:            path=/path/cockroach/cockroach-data
storage engine:      rocksdb
status:              restarted pre-existing node
clusterID:           9ce204b4-4b79-4809-83b5-2dc54c190cb2
nodeID:              1

To connect to this cluster with a socket:

$ cockroach sql --url='postgres://@?host=/tmp&port=26257'

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cockroach sql

Synopsis

Flags

General

Client connection

Logging

Session and output types

SQL shell

Welcome message

Commands

Client-side options

Help

Examples

Shortcuts

Error messages and `SQLSTATE` codes

Examples

Start a SQL shell

Execute SQL statement within the SQL shell

Execute SQL statements from the command line

Control how table rows are printed

Make the output of `SHOW` statements selectable

Execute SQL statements from a file

Run external commands from the SQL shell

Edit SQL statements in an external editor

Allow potentially unsafe SQL statements

Reveal the SQL statements sent implicitly by the command-line utility

Repeat a SQL statement

Connect to a cluster listening for Unix domain socket connections

See also

cockroach sql

Synopsis

Flags

General

Client connection

Logging

Session and output types

SQL shell

Welcome message

Commands

Client-side options

Help

Examples

Shortcuts

Error messages and SQLSTATE codes

Examples

Start a SQL shell

Execute SQL statement within the SQL shell

Execute SQL statements from the command line

Control how table rows are printed

Make the output of SHOW statements selectable

Execute SQL statements from a file

Run external commands from the SQL shell

Edit SQL statements in an external editor

Allow potentially unsafe SQL statements

Reveal the SQL statements sent implicitly by the command-line utility

Repeat a SQL statement

Connect to a cluster listening for Unix domain socket connections

See also

Error messages and `SQLSTATE` codes

Make the output of `SHOW` statements selectable