Whenever I'm using OR in where condition my query is putting date_format() it's working but when I'm using AND it's working fine.
True Query:
SELECT * FROM `tbl_inquiry_trans`
WHERE date_format(follow_updatetime,'%Y-%m-%d') >= '2018-08-02'
AND date_format(follow_updatetime,'%Y-%m-%d') <= '2018-08-02'
AND emp_id=2 or user_id=2
The above query should display specific date data but it's showing all dates data.
Test Query:
SELECT * FROM `tbl_inquiry_trans`
WHERE date_format(follow_updatetime,'%Y-%m-%d') >= '2018-08-02'
AND date_format(follow_updatetime,'%Y-%m-%d') <= '2018-08-02'
AND emp_id=2
When I'm using AND it's showing expected date data but I want to use OR in the where clause.
The and logical operator has a higher precedence than the or operator (i.e., and expressions are evaluated before or expressions, in a similar way you'd calculate a multiplication before calculating an addition in an arithmetic expression). In order to achieve the behavior you wanted, you need to surround the two sides of the or operator with parenthesis:
SELECT *
FROM tbl_inquiry_trans
WHERE date_format(follow_updatetime,'%Y-%m-%d')>='2018-08-02' AND
date_format(follow_updatetime,'%Y-%m-%d')<='2018-08-02' AND
(emp_id=2 OR user_id=2) -- Here
Same answer as #Mureinik, except that I don't think you need to those calls to DATE_FORMAT, because in MySQL it is possible to directly compare dates against string literals. So, the following should suffice:
SELECT *
FROM tbl_inquiry_trans
WHERE
follow_updatetime >= '2018-08-02' AND follow_updatetime < '2018-08-03' AND
(emp_id = 2 OR user_id = 2);
The logic in the above check on follow_updatetime is that any date would match if it were on or after midnight of 2018-08-02 or strictly before midnight of 2018-08-03. This would cover the entire day of 2018-08-02. This version of doing it is preferable to what you had, because it makes it possible to use an index on the follow_updatetime column.
Related
I am having table name as "Table1" in mysql.I have to find Sum of Mean and Std dev on column "Open".I did it easily using python but I am unable to do it using sql.
Select * from BANKNIFTY_cal_spread;
Date Current Next difference
2021-09-03 00:00:00 36914.8 37043.95 129.14999999999418
2021-09-06 00:00:00 36734 36869.15 135.15000000000146
2021-09-07 00:00:00 36572.9 36710.65 137.75
2021-09-08 00:00:00 36945 37065 120
2021-09-09 00:00:00 36770 36895.1 125.09999999999854
Python Code-
nf_fut_mean = round(df['difference'].mean())
print(f"NF Future Mean: {nf_fut_mean}")
nf_fut_std = round(df['difference'].std())
print(f"NF Future Standard Deviation: {nf_fut_std}")
upper_range = round((nf_fut_mean + nf_fut_std))
lower_range = round((nf_fut_mean - nf_fut_std))
I search for Sql solution but I didn't get it. I tried building query but it's not showing correct results in query builder in grafana alerting.
Now I added Mean column ,std dev column , upper_range and lower_range column using python dataframe and pushed to mysql table.
#Booboo,
After removing Date from SQL Query, it's showing correct results in two columns- average + std_deviation and average - std_deviation.
select average + std_deviation, average - std_deviation from (
select avg(difference) as average, stddev_pop(difference) as std_deviation from BANKNIFTY_cal_spread
) sq
It looks as though the sample you're using for the aggregations for MEAN, STDDEV, etc is the entire table - in which case you have to drop the DATE field from the query's result set.
You could also establish the baseline query using a CTE (Common Table Expression) using a WITH statement instead of a subquery, and then apply the subsequent processing:
WITH BN_CTE AS
(
select avg(difference) as average, stddev_pop(difference) as std_deviation from BANKNIFTY_cal_spread
)
select average + std_deviation, average - std_deviation from BN_CTE;
With the data you posted having only a single Open column value for any given Date column value, you standard deviation should be 0 (and the average just that single value).
I am having difficulty in understanding your SQL since I cannot see how it relates to finding the sum (and presumably the difference, which you also seem to want) of the average and standard deviation of column Open in table Table1. If I just go by your English-language description of what you are trying to do and your definition of table Table1, then the following should work. Note that since we want both the sum and difference of two values, which are not trivial to calculate, we should calculate those two values only once:
select Date, average + std_deviation, average - std_deviation from (
select Date, avg(Open) as average, stddev_pop(Open) as std_deviation from Table1
group by Date
) sq
order by Date
Note that I am using column aliases in the subquery that do not conflict with built-in MySQL function names.
SQL does not allow both calculating something in the SELECT clause and using it. (Yes, #variables allow in limited cases; but that won't work for aggregates in the way hinted in the Question.)
Either repeat the expressions:
SELECT average(difference) AS mean,
average(difference) + stddev_pop(difference) AS "mean-sigma",
average(difference) - stddev_pop(difference) AS "mean+sigma"
FROM BANKNIFTY_cal_spread;
Or use a subquery to call the functions only once:
SELECT mean, mean-sigma, mean+sigma
FROM ( SELECT
average(difference) AS mean,
stddev_pop(difference) AS sigma
FROM BANKNIFTY_cal_spread
) AS x;
I expect the timings to be similar.
And, as already mentioned, avoid using aliases that are identical to function names, etc.
I am using DATE() function to calculate the difference between two dates in MySQL
value of SYSDATE() function is following
select SYSDATE();
2020-07-15 12:16:07.0
When I am using date from same month, it is giving correct result
select DATE(SYSDATE())- DATE('2020-07-13');
2
But when I am using date from last month it is giving difference as 86 instead of 16;
select DATE(SYSDATE())- DATE('2020-06-29');
86
Edit:
I am aware that we can use DATEDIFF() but I want to verify why DATE() function is giving results like this since we are already using this in code
MySQL doesn't support subtracting one date from another. The code
SELECT DATE '2020-07-15' - DATE '2020-06-29';
should hence result in an error, but MySQL silently converts this to this instead:
SELECT 20200715 - 20200629;
Seeing that you want to subtract two values, it assumes that you want to work with numbers. Dates are not numbers, but their internal representation yyyymmdd can be represented numerically. So, while CAST(DATE '2020-07-15 ' AS int) fails with a syntax error, as it should, MySQL is not consistent, when it comes to subtraction. It generates the numbers 20200715 and 20200629 and works with these.
I consider this a bug. MySQL should either raise an exception or return an INTERVAL when subtracting one DATE from another.
SELECT * FROM `siparisler` WHERE `cafe_id` = 3 AND DATE_FORMAT(tarih,'%Y-%m-%d') BETWEEN 2017-08-01 AND 2017-08-06
My dates are listed like this on my table (tarih) 2017-02-22 15:28:33
so I want to retrieve data when cafe_id is 3 and tarih between those two dates.
But when I run this query I get zero results.
What may be the problem. I could not find any solution.
DATE_FORMAT() is used on a date data type. You don't need it. You only need the quotes around the constants:
SELECT s.*
FROM siparisler s
WHERE s.cafe_id = 3 AND
s.tarih >= '2017-08-01' AND
s.tarih < '2017-08-07'
Note that I changed the condition from BETWEEN to direct comparisons. This is on purpose. This logic will work regardless of whether tarih has a time component.
You missed to quote the date string literal. It should be
BETWEEN '2017-08-01' AND '2017-08-06'
I am having a table as follows in MYSQL:
proj_id|hoursWorked|Date.
The date field is of type Date; I want to retrieve all the entries from a table depending on a given week number for the project in my java based web application. Please help me to achieve this.
I am unable to write a single query that will allow me to do so.
Do not use something like WHERE WEEK(column)=something - this is a performance killer: It will calculate the week number on all rows, even if they don't match. In addition to that it will make it impossible to use an index ont this column.
Instead calculate an absolute begin and end date or point in time, depending on your data type, then use BETWEEN. This will do no calculations on non-matching rows and allow the use of an index.
Rule of thumb: If you have the choice between a calculation on a constant and on a field, use the former.
use MySQL WEEK() function.
SELECT WEEK(dateColumn)
FROM...
WHERE WEEK(dateColumn) = 1
WEEK()
from MySQL Docs
This function returns the week number for date. The two-argument form
of WEEK() enables you to specify whether the week starts on Sunday or
Monday and whether the return value should be in the range from 0 to
53 or from 1 to 53.
Use WEEK
select * from your_table
where week(`Date`) = week('2012-12-01')
If you want to get only records from the current week you can do
select * from your_table
where week(`Date`) = week(curdate())
I have a field of FromDate and a field of ToDate.
I am looking for the rows that today is between the "from" and "to"
select * from job
where job.type='manager'
and '2014-01-22' between job.FromDate and job.ToDate
The query does not throw an exception , and it even returns some rows. But it isn't right- the rows it returns do not have the dates I am looking for.
P.S. the date format I am using is the correct one for my DB.
Try this
select * from job
where job.type='manager'
and job.FromDate <= '2014-01-22' and job.ToDate >= '2014-01-22'
Comparing dates is often tricky, especially if the values are stored as datetime and not date. The time components can affect the comparison. Another possibility is that ToDate is NULL for the most recent records. Here is one way to fix this:
select *
from job
where job.type ='manager' and
date('2014-01-22') between date(job.FromDate) and date(coalesce(job.ToDate, '2099-12-31'))
However, the use of the function on the columns can make the query less efficient. Instead, you might try:
select *
from job
where job.type ='manager' and
job.FromDate < '2014-01-23' and
(job.ToDate >= '2014-01-22' or job.ToDate is null);