sched.add_job(job_function, CronTrigger.from_crontab('0 0 1-15 may-aug *'))
The above expression is adding a five parameter cron expression, i have an expression like 0 0/1 * 1/1 * ? * which is seven parameter. how to use seven parameter in APScheduler?
Related
I have a string variable stored in hive as follows
stringvar
AA1,BB3,CD4
AA12,XJ5
I would like to count (and filter on) how many times the regex pattern \w\w\d occurs. In the example, in the first row there are obviously three such examples. How can I do that without resorting to lateral views and explosions of stringvar (too expensive)?
Thanks!
You can split string by pattern and calculate size of result array - 1.
Demo:
select size(split('AA1,BB3,CD4','\\w\\w\\d'))-1 --returns 3
select size(split('AA12,XJ5','\\w\\w\\d'))-1 --returns 2
select size(split('AAxx,XJx','\\w\\w\\d'))-1 --returns 0
select size(split('','\\w\\w\\d'))-1 --returns 0
If column is null-able than special care should be taken. For example like this (depends on what you need to be returned in case of NULL):
select case when col is null then 0
else size(split(col,'\\w\\w\\d'))-1
end
Or simply convert NULL to empty string using NVL function:
select size(split(NVL(col,''),'\\w\\w\\d'))-1
The solution above is the most flexible one, you can count the number of occurrences and use it for complex filtering/join/etc.
In case you just need to filter records with fixed number of pattern occurrences or at least fixed number and do not need to know exact count then simple RLIKE without splitting is the cheapest method.
For example check for at least 2 repeats:
select 'AA1,BB3,CD4' rlike('\\w\\w\\d+,\\w\\w\\d+') --returns true, can be used in WHERE
I tried executing the following SQL statement.
SELECT CASE WHEN CHARINDEX('~','test.pdf') > 0
THEN SUBSTRING('test.pdf',CHARINDEX('~', 'test.pdf'), -10)
ELSE NULL
END
This resulted in an error 'Invalid length parameter passed to the substring function.'. However, this was not expected because it is not going to execute anyway.
This query is a simplified version of my requirement. Actually we are computing the value length for the substring. The real scenario is also given below :
SELECT CASE
WHEN CHARINDEX('~', 'test.pdf') > 0 THEN SUBSTRING('test.pdf', CHARINDEX('~', 'test.pdf') + 1, CHARINDEX('~', 'test.pdf', (CHARINDEX('~', 'test.pdf', 1)) + 1) - CHARINDEX('~', 'test.pdf') - 1)
ELSE NULL
END;
In the example its hardcoded as 'test.pdf' but in real scenario it would be values like '111111~22222~33333~4444.pdf' from Table column. Also, I'm not sure this file name should always follow this format. Hence, a validation is required.
Actually, the computation for length is quite expensive, and don't want to use it twice in this query.
You have passed -10 as a constant to substring(). This function does not allow negative values for the third argument:
length
Is a positive integer or bigint expression that specifies how many characters of the expression will be returned. If length is negative, an error is generated and the statement is terminated. If the sum of start and length is greater than the number of characters in expression, the whole value expression beginning at start is returned.
SQL Server catches this problem during the compile phase. This has nothing to do with CASE expression evaluation, but with parsing the expressions.
I have a measurement value(x) that varies between 0 and 500. I would like to use a query to return 1 (Boolean) if this value(x) is below a set value(y) for example 200 and 0 if it is above. I need to do this for a discrete visualization I want to use.
In SQL Server I would use a case expression like
case when col_x < 200 then 1 else 0 end
from <tablename> where <some condition>.
But since Influx has no case expression, I have to use a calculation. In question [52533046][1] it is suggested to use something like
FLOOR(1/(value x/80))
This wont work for example if cpu field is 5. That equation returns 16 so no use as a boolean.
I have an Execute SQL Task that compares 2 snapshot dates and if the date is greater than a month it returns a 1 else it returns a 0. If I use an expression to test for one of the expression I get an advancement in the project however if I test for the other I get no return and the process stops. I have not changed the data so it is testing the same data set. The following are my expression testing:
#[User::MonthFlag] =="1"
#[User::MonthFlag] =="0"
The month Flag is what I am using to pass out as my result set. Heres the query I used:
if (datediff(mm,#maxdw01,#maxas48)=1)
begin
select 1 as MonthFlag
end else
select 0 as MonthFlag
End
UPDATE Table SET Value = 5 WHERE DateTime = '03:42:34';
Sometimes that DateTime will not exist, though. I'm wondering if there's any way that I can have it dynamically attempt then
UPDATE Table SET Value = 5 WHERE DateTime = '03:42:35';
This is probably not possible, especially since 'DateTime` is a string, but wondered if there might be some way of doing it.
I had thought of taking the first 7 characters of the DateTime and having that match, but that's probably not quite precise enough.
The CASE expression sounds like it could do what you want.
A CASE expression serves a role
similar to IF-THEN-ELSE in other
programming languages.
The optional expression that occurs in
between the CASE keyword and the first
WHEN keyword is called the "base"
expression. There are two basic forms
of the CASE expression: those with a
base expression and those without.
In a CASE without a base expression,
each WHEN expression is evaluated and
the result treated as a boolean,
starting with the leftmost and
continuing to the right. The result of
the CASE expression is the evaluation
of the THEN expression that
corresponds to the first WHEN
expression that evaluates to true. Or,
if none of the WHEN expressions
evaluate to true, the result of
evaluating the ELSE expression, if
any. If there is no ELSE expression
and none of the WHEN expressions are
true, then the overall result is NULL.
http://www.sqlite.org/lang_expr.html
Is this what you want?
UPDATE Table
SET Value = 5
WHERE DateTime =
( SELECT MIN(DateTime)
FROM Table
WHERE DateTime >= '03:42:34'
)
;
I got this working in a straightforward way I feel silly for not thinking of originally:
UPDATE Table SET Value = 5 WHERE DateTime BETWEEN datetime('2020-03-21 03:42:35', '-1 second') and datetime('2020-03-21 03:42:35', '+1 second')