I have a text as
Revision:3336179e1ebaa646cf281b7fb9ff36d1b23ce710$ modified $RevDate:10-04-2017 11:43:47$ by $Author:admin
Could you help me out with writing sql query that would get the first 6 chars of revision (333617) and date of RevDate (10-04-2017 11:43:47)? Thanks in advance.
I tried to get revision as
select (regexp_matches ('$Revision:3336179e1ebaa646cf281b7fb9ff36d1b23ce710$ modified $RevDate:10-04-2017 11:43:47$ by $Author:admin$',
'^\$Revision:(a-z0-9+)\$'))[1]
No luck
I'd rather go with substr and split_part (they are faster if I'm not mistaken):
t=# with v as (select 'Revision:3336179e1ebaa646cf281b7fb9ff36d1b23ce710$ modified $RevDate:10-04-2017 11:43:47$ by $Author:admin'::text l)
select substr(l,length('Revision:')+1,6),substr(split_part(l,'$',3),length('RevDate:')+1)
from v;
substr | substr
--------+---------------------
333617 | 10-04-2017 11:43:47
(1 row)
If regular expressions are preferred, the fixed-up expression would be:
select a[1] as revision, a[2] as date from (
select regexp_matches('$Revision:3336179e1ebaa646cf281b7fb9ff36d1b23ce710$ modified $RevDate:10-04-2017 11:43:47$ by $Author:admin$',
'Revision:([a-z0-9]{6}).*RevDate:([^\$]+)') a ) atbl;
Related
I am working on converting something from Oracle to PostgreSQL. In the Oracle file there is a function:
instr(string,substring,starting point,nth location)
Example:
instr(text, '$', 1, 3)
In PostgreSQL this does not exist, so I looked up an equivalent function (4 parameter is important).
I found:
The function strpos(str, sub) in Postgres is equivalent of instr(str, sub) in Oracle. Tried options via split_part (it didn't work out).
I need the same result only with standard functions Postgres (not own function).
Maybe someone will offer options, even redundant in code.
This may be done in pure SQL using string_to_array.
with tab(val) as (
select 'qwe$rty$123$456$78'
union all
select 'qwe$rty$123$'
union all
select '123$456$'
union all
select '123$456'
)
select
val
/*Oracle's signature: instr(string , substring [, position [, occurrence ] ])*/
, case
when
array_length(
string_to_array(substr(val /*string*/, 1 /*position*/), '$' /*substring*/),
1
) <= 3 /*occurrence*/
then 0
else
length(array_to_string((
string_to_array(substr(val /*string*/, 1 /*position*/), '$' /*substring*/)
)[:3/*occurrence*/],
'$'/*substring*/)
) + 1
end as instr
from tab
val
instr
qwe$rty$123$456$78
12
qwe$rty$123$
12
123$456$
0
123$456
0
Postgres: fiddle
Oracle: fiddle
I am running Postgres 9.6
I have a list of various class codes.
Here is:
'What I have' And 'What I Want'
what I have --> what I want.
Equip:Mold --> Equip:Mold
Raw:Resin:TPA --> Raw:Resin
FG --> FG
...
My strategy to accomplish this is to write a user defined function that will find the character count 2nd ':' in my list then use the LEFT function with a LEFT('Raw:Resin:TPA',nthpositionget('Raw:Resin:TPA',':',2))
I tried using the following question to no avail.
Postgres: extract text up to the Nth Character in a String
This overall problem is best handled with regexp_replace():
select regexp_replace('Raw:Resin:TPA', '(^.*:.*):', '\1');
regexp_replace
----------------
Raw:ResinTPA
(1 row)
select regexp_replace('Equip:Mold', '(^.*:.*):', '\1');
regexp_replace
----------------
Equip:Mold
(1 row)
select regexp_replace('FG', '(^.*:.*):', '\1');
regexp_replace
----------------
FG
(1 row)
If you want something that finds the nth occurrence of a substring, then something like this could be made into a function:
with invar as (
select 'Raw:Resin:TPA' as a, ':' as d
)
select case
when length(array_to_string((string_to_array(a, d))[1:2], d)) = length(a) then -1
else length(array_to_string((string_to_array(a, d))[1:2], d)) + 1
end
from invar;
I have 2 varchar(64) values that are decimals in this case (say COLUMN1 and COLUMN2, both varchars, both decimal numbers(money)). I need to create a where clause where I say this:
COLUMN1 < COLUMN2
I believe I have to convert these 2 varchar columns to a different data types to compare them like that, but I'm not sure how to go about that. I tried a straight forward CAST:
CAST(COLUMN1 AS DECIMAL(9,2)) < CAST(COLUMN2 AS DECIMAL(9,2))
But I had to know that would be too easy. Any help is appreciated. Thanks!
You can create a UDF like this to check which values can't be cast to DECIMAL
CREATE OR REPLACE FUNCTION IS_DECIMAL(i VARCHAR(64)) RETURNS INTEGER
CONTAINS SQL
--ALLOW PARALLEL -- can use this on Db2 11.5 or above
NO EXTERNAL ACTION
DETERMINISTIC
BEGIN
DECLARE NOT_VALID CONDITION FOR SQLSTATE '22018';
DECLARE EXIT HANDLER FOR NOT_VALID RETURN 0;
RETURN CASE WHEN CAST(i AS DECIMAL(31,8)) IS NOT NULL THEN 1 END;
END
For example
CREATE TABLE S ( C VARCHAR(32) );
INSERT INTO S VALUES ( ' 123.45 '),('-00.12'),('£546'),('12,456.88');
SELECT C FROM S WHERE IS_DECIMAL(c) = 0;
would return
C
---------
£546
12,456.88
It really is that easy...this works fine...
select cast('10.15' as decimal(9,2)) - 1
from sysibm.sysdummy1;
You've got something besides a valid numerical character in your data..
And it's something besides leading or trailing whitespace...
Try the following...
select *
from table
where translate(column1, ' ','0123456789.')
<> ' '
or translate(column2, ' ','0123456789.')
<> ' '
That will show you the rows with alpha characters...
If the above does't return anything, then you've probably got a string with double decimal points or something...
You could use a regex to find those.
There is a built-in ability to do this without UDFs.
The xmlcast function below does "safe" casting between (var)char and decfloat (you may use as double or as decimal(X, Y) instead, if you want). It returns NULL if it's impossible to cast.
You may use such an expression twice in the WHERE clause.
SELECT
S
, xmlcast(xmlquery('if ($v castable as xs:decimal) then xs:decimal($v) else ()' passing S as "v") as decfloat) D
FROM (VALUES ( ' 123.45 '),('-00.12'),('£546'),('12,456.88')) T (S);
|S |D |
|---------|------------------------------------------|
| 123.45 |123.45 |
|-00.12 |-0.12 |
|£546 | |
|12,456.88| |
i have a starting table where there are some meteo data stored every 15 minutes, one field stores leaf wet at 1 minute sampling in a numeric array form, thus i have a 15 values array each row.
Now i want to create a 1 hour aggregation of this table, crating an array of 60 values for this field.
I tried array_cat at first place, but says
array_cat(numeric[]) not existing
the function obviuously exists, so i tought the format was not the one expected, i tried first unnesting and then aggregating, not working again.
Finally i was able to aggregate trough string conversion, but it's not what i wanted (i might in the future apply some numeric elaboration oh that 60-values array)
I paste the query for further investigations
SELECT dati1_v.id_stazione,
to_char(dati1_v.data_ora, 'YYYY-MM-DD HH24:00:00'::text) AS date_hour,
round(avg(dati1_v.temp1_media), 2) AS t_avg,
round(avg(dati1_v.ur1_media), 2) AS hum_avg,
sum(dati1_v.pioggia) AS rain_tot,
max(dati1_v.pioggia) AS rain_max,
round((avg((SELECT avg(lw.lw) AS avg FROM unnest(dati1_v.lw_top_array) lw(lw))) - lws.top_min) /
(lws.top_max - lws.top_min) * 100::numeric, 2) AS lw_top_avg,
array_agg((SELECT round((avg(lw.lw) - lws.top_min) / (lws.top_max - lws.top_min) * 100::numeric, 2) AS round
FROM unnest(dati1_v.lw_top_array) lw(lw))) AS lw_top_array,
array_cat(dati1_v.lw_top_array) AS lw_top_array_tot,
-- array_agg((select lw_top_array from unnest(dati1_v.lw_top_array))) AS lw_top_array_tot,
-- array_agg(array_to_string(dati1_v.lw_top_array, ',')) AS lw_top_array_tot,
round((avg((SELECT avg(lw.lw) AS avg FROM unnest(dati1_v.lw_bottom_array) lw(lw))) - lws.bottom_min) /
(lws.bottom_max - lws.bottom_min) * 100::numeric, 2) AS lw_bottom_avg,
array_agg((SELECT round((avg(lw.lw) - lws.bottom_min) / (lws.bottom_max - lws.bottom_min) * 100::numeric,
2) AS round
FROM unnest(dati1_v.lw_bottom_array) lw(lw))) AS lw_bottom_array
FROM dati1_v,
lw_settings lws
WHERE lws.id = 1
GROUP BY dati1_v.id_stazione, to_char(dati1_v.data_ora, 'YYYY-MM-DD HH24:00:00'::text), lws.top_min, lws.top_max,
lws.bottom_min, lws.bottom_max
ORDER BY dati1_v.id_stazione, to_char(dati1_v.data_ora, 'YYYY-MM-DD HH24:00:00'::text)
in particular, my tries were related to this specific block:
array_cat(dati1_v.lw_top_array) AS lw_top_array_tot,
-- array_agg((select lw_top_array from unnest(dati1_v.lw_top_array))) AS lw_top_array_tot,
-- array_agg(array_to_string(dati1_v.lw_top_array, ',')) AS lw_top_array_tot
Thanks
For me in similar case helped UNNEST in subquery and ARRAY_AGG of unnnested
SELECT
ARRAY_AGG(
DISTINCT lw_top
) as lw_top_array
FROM (
SELECT
UNNEST(lw_top_array) AS lw_top
FROM
dati1_v
) as tmp;
for me helped next query
SELECT
my_table.key,
array_agg(_unnested.item) as array_coll
from my_table
left join LATERAL (SELECT unnest(my_table.array_coll) as item) _unnested ON TRUE
GROUP by my_table.key
In PostgreSQL, the Group_concat function is not available but you can get similar result as string_agg and array_to_string.
string_agg(array_to_string(file_ids, ','), ',') filter ( where file_ids notnull ) AS file_ids_str
array_to_string and array_to_string works in next way
array_to_string([1, 2, 456], ',') => '1,2,456'
string_agg(['a', 'ab'], ',') => 'a,ab'
the only problem is that result is string with ',' as separator
I want to fetch the names of employees from a table upto the character ':' but couldn't as substr and ltrim is not working as expected. Below given are given some examples:
ABINERI:REBECCA C
CARRINGTON:JAMES M
But I want them in the way given below:
REBECCA C ABINERI
JAMES M CARRINGTON
I just used the query below in Toad for Oracle:
<pre>
<b>select name from employees</b>
</pre>
Please try below query:
select SUBSTR(name,(INSTR(name,':')+1)) || ' ' || SUBSTR(name,1,(INSTR(name,':'))-1) from employees;
hope above query will resolve your issue.