I have a bunch of records in the format of
DATE TYPE
---------- ------
06/21/2014 TYPE A
06/22/2014 TYPE A
06/23/2014 TYPE A
06/24/2014 TYPE B
06/25/2014 TYPE C
06/26/2014 TYPE C
06/27/2014 TYPE A
...
I would like to print out a report that showed the range of type where these parameters existed in sequence.
START END LENGTH
---------- ---------- ------
TYPE A 06/21/2014 06/23/2014 3
TYPE B 06/24/2014 06/24/2014 1
TYPE C 06/25/2014 06/26/2014 2
TYPE A 06/27/2014 06/27/2014 1
Is there any way to display the data in this format from the schema I have been given?
Try the following:
1) Create a group by "type". In the group expert, configure it so that it will not order the result (i think it is called "in original order").
2) Suppress the detail section.
3) In the group footer, show the "type" field, put a summarize of minimum "date" (the start), put a summarize of maximum "date" (the end), put a summarize of count (the length).
Related
I am trying make a function for the aggregate consumption by mid in a kdb+ table (aggregate value by mid). Also this table is being imported from a csv file like this:
table: ("JJP";enlist",")0:`:data.csv
Where the meta data is for the table columns is:
mid is type long(j), value(j) is type long and ts is type timestamp (p).
Here is my function:
agg: {select avg value by mid from table}
but I get the
'type
[0] get select avg value by mid from table
But the type of value is type long (j). So I am not sure why I can't get the avg I also tried this with type int.
Value can't be used as a column name because it is keyword used in kdb+. Renaming the column should correct the issue.
value is a keyword and should not be used as a column name.
https://code.kx.com/q/ref/value/
You can remove it as a column name using .Q.id
https://code.kx.com/q/ref/dotq/#qid-sanitize
q)t:flip`value`price!(1 2;1 2)
q)t
value price
-----------
1 1
2 2
q)t:.Q.id t
q)t
value1 price
------------
1 1
2 2
Or xcol
https://code.kx.com/q/ref/cols/#xcol
q)(enlist[`value]!enlist[`val]) xcol t
val price
---------
1 1
2 2
You can rename the value column as you read it:
flip`mid`val`ts!("JJP";",")0:`:data.csv
q)sym:`a`b`c
q)t:([] s:`g`v; p:2?10.)
Selecting the variable sym works fine in the following query :
q)select sym from t
However it throws an error while selecting with a table column, I am not able to figure out the reason
q)select sym, p from t
You get a 'length error because the lists sym and p (column from t) are different lengths.
q)sym:`a`b
q)select sym,p from t
sym p
------------
a 3.927524
b 5.170911
What is the output you are trying to get to with this?
Assuming you are trying to select as many elements of sym as the table count :
q)select p,(count i)#sym from t
p sym
------------
1.780839 a
3.017723 b
I have a table and want update query to update dob
------------
dob
------------
19101984
19111984
19071985
19081985
19101985
19121985
I want to remove sub string from position 5 to character length of 2 means in the result table will be :
------------
dob
------------
191084
191184
190785
190885
191085
191285
Use regex_replace:
select regexp_replace(dob::text, '(\d{4})\d{2}(\d{2})', E'\\1\\2')
from your_table;
For updating:
update your_table
set dob = regexp_replace(dob, '(\d{4})\d{2}(\d{2})', E'\\1\\2');
The regex pattern being used here is:
(\d{4})\d{2}(\d{2})
^^^^ ^^^^ <-- capture groups
The first four and last two digits are captured in groups 1 and 2, respectively. Then, we simply replace with the first and second capture group.
It is not clear whether the dob column is text or not. If it is numeric, then you should be able to cast to text and run the above query.
Demo
If this is the dictionary of constraint:
dictName:`region`Code;
dictValue:(`NJ`NY;`EEE213);
dict:dictName!dictValue;
I would like to pass the dict to a function and depending on how many keys there are and let the query react accordingly. If there is one key region, then I would like to put it as
select from table where region in dict`region;
The same thing is for code. But if I pass two keys, I would like the query knows and pass it as:
select form table where region in dict`region,Code in dict`code;
Is there any way to do this?
I came up this code:
funcForOne:{[constraint]?[`bce;enlist(in;constraint;(`dict;enlist constraint));0b;()]};
funcForAll[]
{[dict]$[(null dict)~1;select from bce;($[(count key dict)=1;($[`region in (key dict);funcForOne[`region];funcForOne[`Code]]);select from bce where region in dict`region,rxmCode in dict`Code])]};
It works for one and two constraint. but when I called funcForAll[] it gives type error. How should I change it? i think it is from null dict~1
I tried count too. but doesn't work too well.
Update
So I did this but I have some error
tab:([]code:`B90056`B90057`B90058`B90059;region:`CA`NY`NJ`CA);
dictKey:`region`Code;dictValue:(`NJ`NY;`B90057);
dict:dictKey!dictValue;
?[tab;f dict;0b;()];
and I got 'NY error. Do you know why? Also,if I pass a null dictionary it doesn't seem working.
As I said funtional form would be the better approach but if your requirement is very limited as you said then you can consider other solution as below:
Note: Assuming all dictionary keys will be in table columns list.
q) f:{[dict] if[0=count dict;:select from t];
select from t where (#[key dict;t]) in {$[any 0<=type each value x;flip ;enlist ]x}[dict] }
Explanation:
1. convert dict to table depending on the values type. Flip if any value is a general list else enlist.
$[any 0<=type each value dict;flip ;enlist ]dict
Get subset of table t which consists only of dictionary keys as columns.
#[key dict;t]
get rows where (2) in (1)
Basically we are using below form of querying and matching:
q)t1:([]id:1 2;s:`a`b);
q)t2:([]id:1 3 ;s:`a`b);
q)select from t1 where ([]id;s) in t2
If you're just using in, you can do something like:
f:{{[x;y](in),'key[y],'(),x}[;x]enlist each value[x]}
So that:
q)d
a| 10 1
b| ,`a
q)f d
in `a 10 1
in `b ,`a
q)t
a b c
------
1 a 10
2 b 20
3 c 30
q)?[t;f d;0b;()]
a b c
------
1 a 10
Note that because of the enlist each the resulting list is enlisted so that singletons work too:
q)d:enlist[`a]!enlist 1
q)d
a| 1
q)?[t;f d;0b;()]
a b c
------
1 a 10
Update to secondary question
This still works with empty dict, i.e. ()!(). I'm passing in the dictionary variable.
In your 2nd question your dictionary is not constructed correctly (also remember q is case sensitive). Also your values need to be enlisted. Look up functional select in the reference pages on the kx site, you'll see that you need to enlist the symbol lists to differentiate them from column name declarations
`region`code!(enlist `NY`NJ;enlist `B90057)
I have a table that contains a column that has data in the following format - lets call the column "title" and the table "s"
title
ab.123
ab.321
cde.456
cde.654
fghi.789
fghi.987
I am trying to get a unique list of the characters that come before the "." so that i end up with this:
ab
cde
fghi
I have tried selecting the initial column into a table then trying to do an update to create a new column that is the position of the dot using "ss".
something like this:
t: select title from s
update thedot: (title ss `.)[0] from t
i was then going to try and do a 3rd column that would be "N" number of characters from "title" where N is the value stored in "thedot" column.
All i get when i try the update is a "type" error.
Any ideas? I am very new to kdb so no doubt doing something simple in a very silly way.
the reason why you get the type error is because ss only works on string type, not symbol. Plus ss is not vector based function so you need to combine it with each '.
q)update thedot:string[title] ss' "." from t
title thedot
---------------
ab.123 2
ab.321 2
cde.456 3
cde.654 3
fghi.789 4
There are a few ways to solve your problem:
q)select distinct(`$"." vs' string title)[;0] from t
x
----
ab
cde
fghi
q)select distinct(` vs' title)[;0] from t
x
----
ab
cde
fghi
You can read here for more info: http://code.kx.com/q/ref/casting/#vs
An alternative is to make use of the 0: operator, to parse around the "." delimiter. This operator is especially useful if you have a fixed number of 'columns' like in a csv file. In this case where there is a fixed number of columns and we only want the first, a list of distinct characters before the "." can be returned with:
exec distinct raze("S ";".")0:string title from t
`ab`cde`fghi
OR:
distinct raze("S ";".")0:string t`title
`ab`cde`fghi
Where "S " defines the types of each column and "." is the record delimiter. For records with differing number of columns it would be better to use the vs operator.
A variation of WooiKent's answer using each-right (/:) :
q)exec distinct (` vs/:x)[;0] from t
`ab`cde`fghi