select
Inlining SQL into shell pipelines
select
imports tabulated data into an in memory sqlite3 database and executes SQL queries against the data. It returns a table of the same data type as the input type
<stdin> -> select * | ... WHERE ... -> <stdout>
select * | ... FROM file[.gz] WHERE ... -> <stdout>
List a count of all the processes running against each user ID:
» ps aux -> select count(*), user GROUP BY user ORDER BY 1
count(*) USER
1 _analyticsd
1 _applepay
1 _atsserver
1 _captiveagent
1 _cmiodalassistants
1 _ctkd
1 _datadetectors
1 _displaypolicyd
1 _distnote
1 _gamecontrollerd
1 _hidd
1 _iconservices
1 _installcoordinationd
1 _mdnsresponder
1 _netbios
1 _networkd
1 _reportmemoryexception
1 _timed
1 _usbmuxd
2 _appleevents
3 _assetcache
3 _fpsd
3 _nsurlsessiond
3 _softwareupdate
4 _windowserver
5 _coreaudiod
6 _spotlight
7 _locationd
144 root
308 foobar
The table created is called main
, however you do not need to include a FROM
condition in your SQL as Murex will inject FROM main
into your SQL if it is missing. In fact, it is recommended that you exclude FROM
from your SQL queries for the sake of brevity.
config
Optionsselect
’s behavior is configurable:
» config -> [ select ]
{
"fail-irregular-columns": {
"Data-Type": "bool",
"Default": false,
"Description": "When importing a table into sqlite3, fail if there is an irregular number of columns",
"Dynamic": false,
"Global": false,
"Value": false
},
"merge-trailing-columns": {
"Data-Type": "bool",
"Default": true,
"Description": "When importing a table into sqlite3, if `fail-irregular-columns` is set to `false` and there are more columns than headings, then any additional columns are concatenated into the last column (space delimitated). If `merge-trailing-columns` is set to `false` then any trailing columns are ignored",
"Dynamic": false,
"Global": false,
"Value": true
},
"print-headings": {
"Data-Type": "bool",
"Default": true,
"Description": "Print headings when writing results",
"Dynamic": false,
"Global": false,
"Value": true
},
"table-includes-headings": {
"Data-Type": "bool",
"Default": true,
"Description": "When importing a table into sqlite3, treat the first row as headings (if `false`, headings are Excel style column references starting at `A`)",
"Dynamic": false,
"Global": false,
"Value": true
}
}
(See below for how to use config
)
At present, select
only supports reading the entire table from stdin before importing that data into sqlite3. There is some prototype code being written to support sequential imports but this is hugely experimental and not yet enabled.
This might make select
unsuitable for large datasets.
This is a very early release so there almost certainly will be bugs hiding. Which is another reason why this is currently only an optional builtin.
If you do run into any issues then please raise them on Github.
select
*
(generic): generic (primitive)config
: Query or define Murex runtime settingscsv
: CSV files (and other character delimited tables)jsonl
: JSON Linesconfig
. Please read for details.This document was generated from builtins/optional/select/select_doc.yaml.
This site's content is rebuilt automatically from murex's source code after each merge to the master
branch. Downloadable murex binaries are also built with the website.
Last built on Thu Aug 15 14:38:34 UTC 2024 against commit 50ed9d650ed9d6df391240d3c2c02e623636e508dfcdad1.
Current version is 6.2.4000 which has been verified against tests cases.