Finding the second last occurrence of a string (date) in Regex - sql

I got the following strings:
(1640.31; 08/19/2016; 09/13/2016;); (250000.0; 09/30/2016; 02/17/2018;); (100000.0; 03/12/2018; 12/31/2025;);
Or
(1000000.0; 05/30/2018; 06/03/2028;);
I need to return this second to last date, so in these cases for example 1: 03/12/2018 and example 2: 05/30/2018.
Because there are a lot of string-parts ending with ; I can't figure quite out how I can get the second to last date.

Below example for BigQuery Standard SQL
#standardSQL
WITH `project.dataset.table` AS (
SELECT '(1640.31; 08/19/2016; 09/13/2016;); (250000.0; 09/30/2016; 02/17/2018;); (100000.0; 03/12/2018; 12/31/2025;);' AS str UNION ALL
SELECT '(1000000.0; 05/30/2018; 06/03/2028;);'
)
SELECT ARRAY_REVERSE(REGEXP_EXTRACT_ALL(str, r'\d\d/\d\d/\d\d\d\d'))[SAFE_OFFSET(1)] dt
FROM `project.dataset.table`
with result:
Row dt
1 03/12/2018
2 05/30/2018
note: above assumes that dates are always in mm/dd/yyyy or dd/mm/yyyy format, but can be adjusted if different

I think this does what you want:
select (select array_agg(val order by o desc limit 2) -- the limit is just for efficiency
from unnest(split(str, ';')) val with offset o
where val like '%/%/%'
)[ordinal(2)] a
from (select '1640.31; 08/19/2016; 09/13/2016;' as str) x;
Note that this also (happens to) work with parentheses, if they are really part of the strings.

Related

ORACLE TO_CHAR SPECIFY OUTPUT DATA TYPE

I have column with data such as '123456789012'
I want to divide each of each 3 chars from the data with a '/' in between so that the output will be like: "123/456/789/012"
I tried "SELECT TO_CHAR(DATA, '999/999/999/999') FROM TABLE 1" but it does not print out the output as what I wanted. Previously I did "SELECT TO_CHAR(DATA, '$999,999,999,999.99') FROM TABLE 1 and it printed out as "$123,456,789,012.00" so I thought I could do the same for other case as well, but I guess that's not the case.
There is also a case where I also want to put '#' in front of the data so the output will be something like this: #12345678901234. Can I use TO_CHAR for this problem too?
Is these possible? Because when I go through the documentation of oracle about TO_CHAR, it stated a few format that can be use for TO_CHAR function and the format that I want is not listed there.
Thank you in advance. :D
Here is one option with varchar2 datatype:
with test as (
select '123456789012' a from dual
)
select listagg(substr(a,(level-1)*3+1,3),'/') within group (order by rownum) num
from test
connect by level <=length(a)
or
with test as (
select '123456789012.23' a from dual
)
select '$'||listagg(substr((regexp_substr(a,'[0-9]{1,}')),(level-1)*3+1,3),',') within group (order by rownum)||regexp_substr(a,'[.][0-9]{1,}') num
from test
connect by level <=length(a)
output:
1st query
123/456/789/012
2nd query
$123,456,789,012.23
If you wants groups of three then you can use the group separator G, and specify the character to use:
SELECT TO_CHAR(DATA, 'FM999G999G999G999', 'NLS_NUMERIC_CHARACTERS=./') FROM TABLE_1
123/456/789/012
If you want a leading # then you can use the currency indicator L, and again specify the character to use:
SELECT TO_CHAR(DATA, 'FML999999999999', 'NLS_CURRENCY=#') FROM TABLE_1
#123456789012
Or combine both:
SELECT TO_CHAR(DATA, 'FML999G999G999G999', 'NLS_CURRENCY=# NLS_NUMERIC_CHARACTERS=./') FROM TABLE_1
#123/456/789/012
db<>fiddle
The data type is always a string; only the format changes.

Regex that matches strings with specific text not between text in BigQuery

I have the following strings:
step_1->step_2->step_3
step_1->step_3
step_1->step_2->step_1->step_3
step_1->step_2->step_1->step_2->step_3
What I would like to do is to capture the ones that between step_1 and step 3 there's no step_2.
The results should be like this:
string result
step_1->step_2->step_3 false
step_1->step_3 true
step_1->step_2->step_1->step_3 true
step_1->step_2->step_1->step_2->step_3 false
I have tried to use the negative lookahead but I found out that BigQuery doesn't support it. Any ideas?
You are essentially looking for when the pattern does not exist. The following regex would support that embedded in a case statement. This would not support a scenario where you have both conditions in a single string, however that was not a scenario you listed in your sample data.
Try the following:
with sample_data as (
select 'step_1->step_2->step_3' as string union all
select 'step_1->step_3' union all
select 'step_1->step_2->step_1->step_3' union all
select 'step_1->step_2->step_1->step_2->step_3' union all
select 'step_1->step_2->step_1->step_2->step_2->step_3' union all
select 'step_1->step_2->step_1->step_2->step_2'
)
select
string,
-- CASE WHEN regexp_extract(string, r'step_1->(\w+)->step_3') IS NULL THEN TRUE
CASE WHEN regexp_extract(string, r'1(->step_2)+->step_3') IS NULL THEN TRUE
ELSE FALSE END as result
from sample_data
This results in:
Consider also below option
select string,
not regexp_contains(string, r'step_1->(step_2->)+step_3\b') as result
from your_table
I believe #Daniel_Zagales answer is the one you were expecting. However here is a broader solution that can maybe be interesting in your usecase:it consists in using arrays
WITH sample AS (
SELECT 'step_1->step_2->step_3' AS path
UNION ALL SELECT 'step_1->step_3'
UNION ALL SELECT 'step_1->step_2->step_1->step_3'
UNION ALL SELECT 'step_1->step_2->step_1->step_2->step_3'
),
temp AS (
SELECT
path,
SPLIT(REGEXP_REPLACE(path,'step_', ''), '->') AS sequences
FROM
sample)
SELECT
path,
position,
flattened AS current_step,
LAG(flattened) OVER (PARTITION BY path ORDER BY OFFSET ) AS previous_step,
LEAD(flattened) OVER (PARTITION BY path ORDER BY OFFSET ) AS following_step
FROM
temp,
temp.sequences AS flattened
WITH
OFFSET AS position
This query returns the following table
The concept is to get an array of the step number (splitting on '->' and erasing 'step_') and to keep the OFFSET (crucial as UNNESTing arrays does not guarantee keeping the order of an array).
The table obtained contains for each path and step of said path, the previous and following step. It is therefore easy to test for instance if successive steps have a difference of 1.
(SELECT * FROM <previous> WHERE ABS(current_step-previous_step) != 1 for example)
(CASTing to INT required)

How can I count repeated values in the string in BigQuery?

Example:
I have the following string:
201904,BLANK,201902,BLANK,BLANK,201811,201810,201809
How can I count the number of repeated values "BLANK" that goes one by one?
In the described example the answer is 2, but what is the query?
Thanks for your help in advance!
Below is for BigQuery Standard SQL (with quick simplified example)
Corrected Version
#standardSQL
WITH `project.dataset.table` AS (
SELECT '201904,BLANK,201902,BLANK,BLANK,201811,201810,201809,BLANK,BLANK,BLANK' value UNION ALL
SELECT '201904,BLANK,201902,BLANK,BLANK,BLANK,201811' UNION ALL
SELECT '201904,BLANK,201902,BLANK,201811,201902,BLANK,201811'
)
SELECT value,
(
SELECT MAX(ARRAY_LENGTH(SPLIT(list))) - 1
FROM UNNEST(REGEXP_EXTRACT_ALL(value || ',', r'(?:BLANK,){1,}')) list
) max_repeated_count
FROM `project.dataset.table`
The idea here is
extract all instances of consecutive BLANK
split each such instances to array of elements of BLANK
and finally get max length of those arrays as a result
Just something came as quick approach
Refactored Version
#standardSQL
WITH `project.dataset.table` AS (
SELECT '201904,BLANK,201902,BLANK,BLANK,201811,201810,201809,BLANK,BLANK,BLANK' value UNION ALL
SELECT '201904,BLANK,201902,BLANK,BLANK,BLANK,201811' UNION ALL
SELECT '201904,BLANK,201902,BLANK,201811,201902,BLANK,201811'
)
SELECT value,
(
SELECT MAX(LENGTH(element) - 1)
FROM UNNEST(REGEXP_EXTRACT_ALL(REPLACE(value || ',', 'BLANK', ''), r',+')) element
) max_repeated_count
FROM `project.dataset.table`
Both with output
Row value max_repeated_count
1 201904,BLANK,201902,BLANK,BLANK,201811,201810,201809,BLANK,BLANK,BLANK 3
2 201904,BLANK,201902,BLANK,BLANK,BLANK,201811 3
3 201904,BLANK,201902,BLANK,201811,201902,BLANK,201811 1
Refactored version is slightly different (but main idea the same)
it removes all BLANKS (assuming BLANK cannot be part of other element - if it can - code can easily be adjusted)
then extract all consecutive entries of commas into array
calculates max length of such sequences of commas
Maybe I misunderstood, but can't you simply split by the value you're looking for and subtract 2 (1 for the first element and 1 for counting elements after splitting):
declare t DEFAULT '201904,BLANK,201902,BLANK,BLANK,201811,201810,201809';
SELECT
t as theString,
split(t,'BLANK') as theSplittedString,
array_length(split(t,'BLANK'))-2 as theAmount
n>0 - amount of repetition,
0 - no repetition,
-1 - element not found

Get group maxima from combined strings

I have a table with a column code containing multiple pieces of data like this:
001/2017/TT/000001
001/2017/TT/000002
001/2017/TN/000003
001/2017/TN/000001
001/2017/TN/000002
001/2016/TT/000001
001/2016/TT/000002
001/2016/TT/000001
002/2016/TT/000002
There are 4 items in 001/2016/TT/000001: 001, 2016, TT and 000001.
How can I extract the max for every group formed by the first 3 items? The result I want is this:
001/2017/TT/000003
001/2017/TN/000002
001/2016/TT/000002
002/2016/TT/000002
Edit
The subfield separator is /, and the length of subfields can vary.
I use PostgreSQL 9.3.
Obviously, you should normalize the table and split the combined string into 4 columns with proper data type. The function split_part() is the tool of choice if the separator '/' is constant in your string and the length of can vary.
CREATE TABLE tbl_better AS
SELECT split_part(code, '/', 1)::int AS col_1 -- better names?
, split_part(code, '/', 2)::int AS col_2
, split_part(code, '/', 3) AS col_3 -- text?
, split_part(code, '/', 4)::int AS col_4
FROM tbl_bad
ORDER BY 1,2,3,4 -- optionally cluster data.
Then the task is trivial:
SELECT col_1, col_2, col_3, max(col_4) AS max_nr
FROM tbl_better
GROUP BY 1, 2, 3;
Related:
Split comma separated column data into additional columns
Of course, you can do it on the fly, too. For varying subfield length you could use substring() with a regular expression like this:
SELECT max(substring(code, '([^/]*)$')) AS max_nr
FROM tbl_bad
GROUP BY substring(code, '^(.*)/');
Related (with basic explanation for regexp pattern):
Filter strings with regex before casting to numeric
Or to get only the complete string as result:
SELECT DISTINCT ON (substring(code, '^(.*)/'))
code
FROM tbl_bad
ORDER BY substring(code, '^(.*)/'), code DESC;
About DISTINCT ON:
Select first row in each GROUP BY group?
Be aware that data items cast to a suitable type may behave differently from their string representation. The max of 900001 and 1000001 is 900001 for text and 1000001 for integer ...
Use the LEFT and RIGHT functions.
SELECT MAX(RIGHT(code,6)) AS MAX_CODE
FROM yourtable
GROUP BY LEFT(code,12)
check this out, possible helpfull
select
distinct on (tab[4],tab[2]) tab[4],tab[3],tab[2],tab[1]
from
(
select
string_to_array(exe.x,'/') as tab,
exe.x
from
(
select
unnest
(
array
['001/2017/TT/000001',
'001/2017/TT/000002',
'001/2017/TN/000003',
'001/2017/TN/000001',
'001/2017/TN/000002',
'001/2016/TT/000001',
'001/2016/TT/000002',
'001/2016/TT/000001',
'002/2016/TT/000002']
) as x
) exe
) exe2
order by tab[4] desc,tab[2] desc,tab[3] desc;

SQL Summing digits of a number

i'm using presto. I have an ID field which is numeric. I want a column that adds up the digits within the id. So if ID=1234, I want a column that outputs 10 i.e 1+2+3+4.
I could use substring to extract each digit and sum it but is there a function I can use or simpler way?
You can combine regexp_extract_all from #akuhn's answer with lambda support recently added to Presto. That way you don't need to unnest. The code would be really self explanatory if not the need for cast to and from varchar:
presto> select
reduce(
regexp_extract_all(cast(x as varchar), '\d'), -- split into digits array
0, -- initial reduction element
(s, x) -> s + cast(x as integer), -- reduction function
s -> s -- finalization
) sum_of_digits
from (values 1234) t(x);
sum_of_digits
---------------
10
(1 row)
If I'm reading your question correctly you want to avoid having to hardcode a substring grab for each numeral in the ID, like substring (ID,1,1) + substring (ID,2,1) + ...substring (ID,n,1). Which is inelegant and only works if all your ID values are the same length anyway.
What you can do instead is use a recursive CTE. Doing it this way works for ID fields with variable value lengths too.
Disclaimer: This does still technically use substring, but it does not do the clumsy hardcode grab
WITH recur (ID, place, ID_sum)
AS
(
SELECT ID, 1 , CAST(substring(CAST(ID as varchar),1,1) as int)
FROM SO_rbase
UNION ALL
SELECT ID, place + 1, ID_sum + substring(CAST(ID as varchar),place+1,1)
FROM recur
WHERE len(ID) >= place + 1
)
SELECT ID, max(ID_SUM) as ID_sum
FROM recur
GROUP BY ID
First use REGEXP_EXTRACT_ALL to split the string. Then use CROSS JOIN UNNEST GROUP BY to group the extracted digits by their number and sum over them.
Here,
WITH my_table AS (SELECT * FROM (VALUES ('12345'), ('42'), ('789')) AS a (num))
SELECT
num,
SUM(CAST(digit AS BIGINT))
FROM
my_table
CROSS JOIN
UNNEST(REGEXP_EXTRACT_ALL(num,'\d')) AS b (digit)
GROUP BY
num
;