How to do the count - oracle-apex

I've a code which will provide me count of records. Addition to this I need to know which level the 'Vinod' is there (whether it is in second level, third level or fourth level'). This information needed in label.
Select 'Open' label, count(*) value from DATA
WHERE SECOND_LEVEL = 'vinod' or THIRD_LEVEL = 'vinod' or FOURTH_LEVEL = 'vinod'

See whether this helps; lvl represents your second to fourth level.
with temp as
(select 2 lvl, count(*) cnt
from data
where second_level = 'vinod'
union all
select 3 lvl, count(*) cnt
from data
where third_level = 'vinod'
union all
select 4 lvl, count(*) cnt
from data
where fourth_level = 'vinod'
)
select lvl, sum(cnt) sum_cnt
from temp
group by lvl;
Or this (which might perform better, as the above example queries the same table 3 times):
select case when second_level = 'vinod' then 2
when third_level = 'vinod' then 3
when fourth_level = 'vinod' then 4
end lvl,
count(*) cnt
from data
where 'vinod' in (second_level, third_level, fourth_level)
group by case when second_level = 'vinod' then 2
when third_level = 'vinod' then 3
when fourth_level = 'vinod' then 4
end;

Related

BigQuery compare all the columns(100+) from two rows in a sinle table

I have input table as below-
id
col1
col2
time
01
abc
001
12:00
01
def
002
12:10
Required output table-
id
col1
col2
time
diff_field
01
abc
001
12:00
null
01
def
002
12:10
col1,col2
I need to compare both the rows and find all the columns for which there is difference in value and keep those column names in a new column diff_field.
I need a optimized solution for this as my table has more than 100 columns(all the columns need to be compared)
You might consider below approach:
WITH sample_table AS (
SELECT '01' id, 'abc' col1, '001' col2, '12:00' time UNION ALL
SELECT '01' id, 'def' col1, '002' col2, '12:10' time UNION ALL
SELECT '01' id, 'def' col1, '002' col2, '12:20' time UNION ALL
SELECT '01' id, 'ddf' col1, '002' col2, '12:30' time
)
SELECT * EXCEPT(curr, prev),
(SELECT STRING_AGG('col' || offset)
FROM UNNEST(SPLIT(curr)) c WITH offset
JOIN UNNEST(SPLIT(prev)) p WITH offset USING (offset)
WHERE c <> p AND offset < ARRAY_LENGTH(SPLIT(curr)) - 1
) diff_field
FROM (
SELECT *, FORMAT('%t', t) AS curr, LAG(FORMAT('%t', t)) OVER w AS prev
FROM sample_table t
WINDOW w AS (PARTITION BY id ORDER BY time)
);
Query results
Below approach has no dependency on actual columns' names or any names convention rather then only id and time
create temp function extract_keys(input string) returns array<string> language js as """
return Object.keys(JSON.parse(input));
""";
create temp function extract_values(input string) returns array<string> language js as """
return Object.values(JSON.parse(input));
""";
select t.*,
( select string_agg(col)
from unnest(extract_keys(cur)) as col with offset
join unnest(extract_values(cur)) as cur_val with offset using(offset)
join unnest(extract_values(prev)) as prev_val with offset using(offset)
where cur_val != prev_val and col != 'time'
) as diff_field
from (
select t, to_json_string(t) cur, to_json_string(ifnull(lag(t) over(win), t)) prev
from your_table t
window win as (partition by id order by time)
)
if apply to sample data in your question (or rather extended version of it that I borrowed from Jaytiger answer) - the output is

Fetch values from another table for each column written in an array for each ID

I have a dataset that looks like this
sample_data_1
select 'Alice' AS ID, 2 AS col1, 5 AS col2, 6 AS col3, 0 AS col4
union all
select 'Bob' AS ID, 1 AS col1, 4 AS col2, -2 AS col3, 7 AS col4
and a dataset that looks like this. This provides a list of important columns for each ID
sample_data_2
select 'Alice' AS ID, [STRUCT('col1' AS column, 1 AS rank), STRUCT('col4' AS column, 2 AS rank), STRUCT('col3' AS column, 3 AS rank)] AS important_columns
union all
select 'Bob' AS ID, [STRUCT('col4' AS column, 1 AS rank), STRUCT('col2' AS column, 2 AS rank), STRUCT('col1' AS column, 3 AS rank)]
I would like to add the values of the important columns for each ID from sample_data_1
So I can have an output that looks like this
select 'Alice' AS ID, [STRUCT('col1' AS column, 1 AS rank, 2 AS value), STRUCT('col4' AS column, 2 AS rank, 0 AS value), STRUCT('col3' AS column, 3 AS rank, 6 AS value)] AS important_columns
union all
select 'Bob' AS ID, [STRUCT('col4' AS column, 1 AS rank, 7 AS value), STRUCT('col2' AS column, 2 AS rank, 4 AS value), STRUCT('col1' AS column, 3 AS rank, 1 AS value)]
output
I would like the code to be dynamic, so will work even if column names change or number of columns change
Consider below query.
EXECUTE IMMEDIATE FORMAT("""
CREATE TEMP TABLE sample_data1_unpivoted AS
SELECT ID, ARRAY_AGG(STRUCT(column, value)) outputs FROM sample_data1 UNPIVOT (value FOR column IN (%s)) GROUP BY 1
""", ARRAY_TO_STRING(
REGEXP_EXTRACT_ALL(TO_JSON_STRING((SELECT AS STRUCT * EXCEPT (ID) FROM sample_data1 LIMIT 1)), r'"([^,{]+)":'), ',')
);
SELECT ID, ARRAY (
SELECT AS STRUCT column, rank, value
FROM t1.important_columns LEFT JOIN t2.outputs USING (column)
) important_columns
FROM sample_data2 t1
LEFT JOIN sample_data1_unpivoted t2 USING (ID);
Query results

Oracle - split the string by comma and get the last sub-str

I wanted to write an Oracle query to extract only the last sub-string of comma separated string like below:
DEST = "1,MMA SALAI,ARIANKUPAM,CITY CENTRE,G12 47H"
I am interested in only G12. How do I get in the Oracle query?
Thanks
Try
REGEXP_SUBSTR('1,MMA SALAI,ARIANKUPAM,CITY CENTRE,G12 47H', '[^,]+$')
But that will fetch G12 47H. You may consider
REGEXP_SUBSTR('1,MMA SALAI,ARIANKUPAM,CITY CENTRE,G12 47H', '([^, ]+)( +[^,]*)?$', 1,1,NULL,1)
This will give G12.
A little bit of substringing (see comments within the code):
SQL> with test (dest) as
2 (select '1,MMA SALAI,ARIANKUPAM,CITY CENTRE,G12 47H' from dual)
3 select
4 regexp_substr(dest, --> out of the DEST, give me ...
5 '\w+', --> ... the first word that begins right after ...
6 instr(dest, ',', 1, regexp_count(dest, ',')) + 1 --> ... postition of the last
7 ) result --> comma in the source string
8 from test;
RESULT
--------------------
G12
SQL>
Or, by splitting the comma-separated values into rows:
SQL> with test (dest) as
2 (select '1,MMA SALAI,ARIANKUPAM,CITY CENTRE,G12 47H' from dual)
3 select regexp_substr(col, '\w+') result
4 from (select regexp_substr(dest, '[^,]+', 1, level) col, --> split column to rows
5 row_number() over (order by level desc) rn --> the last row will be RN = 1
6 from test
7 connect by level <= regexp_count(dest, ',') + 1
8 )
9 where rn = 1;
RESULT
--------------------
G12
SQL>

SELECT MAX PARTITION TABLE

I have a table with partition on date(transaction_time), And I have a
problem with a select MAX.
I'm trying to get the row with the highest timestamp if I get more then 1 row in the result on one ID.
Example of data:
1. ID = 1 , Transaction_time = "2018-12-10 12:00:00"
2. ID = 1 , Transaction_time = "2018-12-09 12:00:00"
3. ID = 2 , Transaction_time = "2018-12-10 12:00:00"
4. ID = 2 , Transaction_time = "2018-12-09 12:00:00"
Result that I want:
1. ID = 1 , Transaction_time = "2018-12-10 12:00:00"
2. ID = 2 , Transaction_time = "2018-12-10 12:00:00"
This is my query
SELECT ID, TRANSACTION_TIME FROM `table1` AS T1
WHERE TRANSACTION_TIME = (SELECT MAX(TRANSACTION_TIME)
FROM `table1` AS T2
WHERE T2.ID = T1.ID )
The error I receive:
Error: Cannot query over table 'table1' without a filter over
column(s) 'TRANSACTION_TIME' that can be used for partition
elimination
It looks like BigQuery does not the correlated subquery in the WHERE clause. I don't know how to fix your current approach, but you might be able to just use ROW_NUMBER here:
SELECT t.ID, t.TRANSACTION_TIME
FROM
(
SELECT ID, TRANSACTION_TIME,
ROW_NUMBER() OVER (PARTITION BY ID ORDER BY TRANSACTION_TIME DESC) rn
FROM table1
) t
WHERE rn = 1;
can be done this way:
SELECT id, MAX(transaction_time) FROM `table1` GROUP BY id;

Extract string from a large string oracle regexp

I have String as below.
select b.col1,a.col2,lower(a.col3) from table1 a inner join table2 b on a.col = b.col and a.col = b.col
inner join (select col1, col2, col3,col4 from tablename ) c on a.col1=b.col2
where
a.col = 'value'
Output need to be table1,table2 and tablename from above string. please let me know the regex to get the result.
Should be a simple one :-)
SQL> WITH DATA AS(
2 select q'[select b.col1,a.col2,lower(a.col3) from table1 a inner join table2 b on
3 a.col = b.col and a.col = b.col inner join (select col1, col2, col3,col4 from tablename )
4 c on a.col1=b.col2 where a.col = 'value']' str
5 FROM DUAL)
6 SELECT LISTAGG(TABLE_NAMES, ' , ') WITHIN GROUP (
7 ORDER BY val) table_names
8 FROM
9 (SELECT 1 val,
10 regexp_substr(str,'table[[:alnum:]]+',1,level) table_names
11 FROM DATA
12 CONNECT BY level <= regexp_count(str,'table')
13 )
14 /
TABLE_NAMES
--------------------------------------------------------------------------------
table1 , table2 , tablename
SQL>
Brief explanation, so that OP/even others might find it useful :
The REGEXP_SUBSTR looks for the words 'table', it could be followed
by a number or string like 1,2, name etc.
To find all such words, I used connect by level technique, but it
gives the output in different rows.
Finally, to put them in a single row as comma separated values, I
used LISTAGG.
Oh yes, and that q'[]' is the string literal technique.