How to query data from timestamp column with delay.? - derby

I want a query to get data from a derby table with the timestamp where time value is less than two hours to current time. following query gives and error saying
operator with a left operand type of 'TIMESTAMP' and a right operand type of 'INTEGER' is not supported.
Query:
select * from NEWS WHERE NEWS_DATE < current_timestamp-2
Appriciate any help

Here is the answer,
select *from NEWS where {fn TIMESTAMPDIFF( SQL_TSI_MINUTE, NEWS_DATE,current_timestamp)} <120

Related

Getting error in vertica:For 'IN', types varchar and int are inconsistent DETAIL: Columns: unknown and unknown

I am trying to execute below query in vertica:
select case
when to_char(to_date('02-15-2017','mm-dd-yyyy'),'mm')in(1,2,3,4,5,6,7,8,9,10) then
(select to_char(add_months(trunc(to_date('02-15-2017','mm-dd-yyyy'),'year'),-2),'mm-dd-yyyy') from dual);
else
(select to_char(add_months(trunc(to_date('02-15-2017','mm-dd-yyyy'),'year'),10),'mm-dd-yyyy') from dual)
end ett from dual;
Query is getting expected results in oracle but in Vertica Getting error
:For 'IN', types varchar and int are inconsistent DETAIL: Columns:
unknown and unknown.
Expected Result is fiscal Start date as 1st Nov 2016.
The base problem is that you are comparing a string to a number in your IN() predicate. (TO_CHAR() with a list of numbers). While Oracle (which your used syntax suggests) often implicitly converts data types to make a comparison happen, Vertica, like most other more ANSI compliant databases, is much stricter.
And you could have written your statement in a more concise way:
You don't need the FROM dual clause in Vertica (even if it implicitly adds it internally)
You wouldn't even have to nest the SELECTS in Oracle; it's enough to SELECT the whole CASE expression.
You could formulate the date literals much easier, by using the ISO format and preceding that string with the DATE keyword.
So, in general, I'd have written it like so:
SELECT
CASE
WHEN MONTH(DATE '2017-02-15') <= 10
THEN TO_CHAR(ADD_MONTHS(TRUNC(DATE '2017-02-05','YEAR'), -2),'mm-dd-yyyy')
ELSE TO_CHAR(ADD_MONTHS(TRUNC(DATE '2017-02-05','YEAR'), 10),'mm-dd-yyyy')
END AS ett
;

Searching first condition first and only if not available then second condition

I am writing an SQL query where the query should first search the first value, and only if this value is missing the query should search for the second value.
I have two tables. One of these tables contains the modification date (this is not always filled and can be null) and a creation date which is always filled.
Now what I want is that the query first looks in the table with the modification date and only if it is null looks at the table with the creation date.
Example of the query:
Select *
from all_articles
where to_char(modification_date, 'YYYYMMDD') = to_char(sysdate, 'YYYYMMDD')-1
-- if this is an empty record then
to_char(creation_date, 'YYYYMMDD') = to_char(sysdate, 'YYYYMMDD')-1
Can anyone help me with this query?
Almost all the major RDBMS' available have in built functions to handle such a situation.
The Oracle DB has NVL function which works as follows:
NVL(Modified_dt, Create_dt);
The above will return Modified_dt column data by default. However, if that isn't available, it will return Create_dt.
See here for details:
http://www.w3schools.com/sql/sql_isnull.asp

Compare date to month-year in Postgres/Ruby

I have a date column in my table and I would like to 'filter'/select out items after a certain year-month. So if I have data from 2010 on, I have a user input that specifies '2011-10' as the 'earliest date' they want to see data from.
My current SQL looks like this:
select round(sum(amount), 2) as amount,
date_part('month', date) as month
from receipts join items
on receipts.item = items.item
where items.expense = ?
and date_part('year', date)>=2014
and funding = 'General'
group by items.expense, month, items.order
order by items.order desc;
In the second part of the 'where', instead of doing year >= 2014, I want to do something like to_char(date, 'YY-MMMM') >= ? as another parameter and then pass in '2011-10'. However, when I do this:
costsSql = "select round(sum(amount), 2) as amount,
to_char(date, 'YY-MMMM') as year_month
from receipts join items
on receipts.item = items.item
where items.expense = ?
and year_month >= ?
and funding = 'General'
group by items.expense, year_month, items.order
order by items.order desc"
and call that with my two params, I get a postgres error: PG::UndefinedColumn: ERROR: column "year_month" does not exist.
Edit: I converted my YYYY-MM string into a date and passed that in as my param instead and it's working. But I still don't understand why I get the 'column does not exist' error after I created that column in the select clause - can someone explain? Can columns created like that not be used in where clauses?
This error: column "year_month" does not exist happens because year_month is an alias defined the SELECT-list and such aliases can't be refered to in the WHERE clause.
This is based on the fact that the SELECT-list is evaluated after the WHERE clause, see for example: Column alias in where clause? for an explanation from PG developers.
Some databases allow it nonetheless, others don't, and PostgreSQL doesn't. It's one of the many portability hazards between SQL engines.
In the case of the query shown in the question, you don't even need the to_char in the WHERE clause anyway, because as mentioned in the first comment, a direct comparison with a date is simpler and more efficient too.
When a query has a complex expression in the SELECT-list and repeating it in the WHERE clause looks wrong, sometimes it might be refactored to move the expression into a sub-select or a WITH clause at the beginning of the query.

compare 13digit (millisecond) unix timestamp with date in oracle

A database column (VARCHAR2 datatype) stores the date/time as 13 digit (milliseconds
) unixtimestamp format. Now when I want to compare the column with a oracle date (in question), The error thrown as 'invalid number'
I tried both ways,
converting the 13digit number to Date and compare with the date in question like below. The expressions seems valid as they are printed in select query, but if i include in the where part, it throws 'invalid number'
Here 'value' is 13th digit unixtimestamp column of VARCHAR2 datatype.
select
TO_DATE('1970-01-01', 'YYYY-MM-DD') + value/86400000,
TO_DATE('2014-04-21', 'YYYY-MM-DD')
from dummytable
-- where and TO_DATE('1970-01-01', 'YYYY-MM-DD') + value/86400000 > TO_DATE('2014-04-21', 'YYYY-MM-DD')
converting the date in question to 13digit unixtimestamp and comparing with the database column.The expressions seems valid as they are printed in select query, but if i include in the where part, it throws 'invalid number'
.
select
value,
(to_date('2013-04-21', 'YYYY-MM-DD') - to_date('1970-01-01', 'YYYY-MM-DD')) * (1000*24*60*60)
from dummytable
-- where value > ((to_date('2013-04-21', 'YYYY-MM-DD') - to_date('1970-01-01', 'YYYY-MM-DD')) * (1000*24*60*60))
any pointers? Thanks in advance.
[EDIT- 1 day later] I see the problem now. There are some data (other rows) for the 'value' column that are non-numeric. But I have another column say field, where always field='date' return value as 13 digit timestamp. Now I think when 'where' condition executes, although the field='date' is in the condition, it is still validating the other values for 'value' which are non-numeric. Is there a way to avoid this ?
Your code works just fine. The problem is in your data. Some of your values is not a number.
create table test
(value varchar2(13));
insert into test(value) values('2154534689000');
--insert into test(value) values('2 54534689000');
select TO_DATE('1970-01-01', 'YYYY-MM-DD') + value/86400000
from test
where TO_DATE('1970-01-01', 'YYYY-MM-DD') + value/86400000 > TO_DATE('2014-04-21', 'YYYY-MM-DD');
This code works fine. But if you uncommented the second insert, you would get exactly the same invalid number error as you get.
UPD. Allan gave you a nice hint, but i feel that it can be good to explain you a bit about views. The fact that you select from a view CAN make a difference. A view is not stored somewhere physically, when you select from it, it is just "added to your query". And then Oracle Query Optimizer starts working. Among other things, it can change the order in which your where predicates are evaluated.
For example, your the view query can have a line where value is not null and it would normally show only 'good' values. But if your query has a predicate where to_date(value,'ddmmyyyy') > sysdate, Oracle can decide to evaluate your predicate earlier, because Oracle predicts that it would "cut off" more rows, thus making the whole query faster and less momery consuming. Of course, execution will crash because of an attempt to convert a null string to date.
I believe, that Allan in his answer that he gave a link to, gave a great way to solve this problem: "wrapping" your query in a subquery that Oracle can't "unwrap":
select value
from
(select value
from my_view
where rownum > 0)
where to_date(value,'ddmmyyyy') > sysdate
Hope that helps.

oracle query error: exact fetch return more than requested no of rows

I have two tables seatinfo(siid,seatno,classid,tsid) and booking (bookid,siid,date,status).
I've input parameter bookDate,v_tsId ,v_clsId. I need exactly one row (bookid) to return. This query is not working. I don't no why. How can I fix it?
select bookid
into v_bookid
from booking
where (to_char(booking.bookdate,'dd-mon-yy'))=(to_char(bookDate,'dd-mon-yy'))
and status=0
and rownum <= 1
and siid in(select siid
from seatinfo
where tsid=v_tsId
and classid= v_clsId);
I also tried this:
select bookid
into v_bookid
from booking,
seatinfo
where booking.siid=seatinfo.siid
and (to_char(booking.bookdate,'dd-mon-yy'))=(to_char(bookDate,'dd-mon-yy'))
and booking.status=0
and rownum <= 1
and seatinfo.tsid=v_tsId
and seatinfo.classid= v_clsId;
Are you saying that you get an "ORA-01422: exact fetch returns more than requested number of rows" when you run both of those queries? That seems highly unlikely since you're including the predicate rownum <= 1. Can you cut and paste from a SQL*Plus session that runs just this query in a PL/SQL block and generates the error?
If you are not complaining about the error you mention in the title, and the problem is just that you're not getting the data you expect, the likely problem is that you apparently have a bookDate parameter that has the same name as a column in your table. That is not going to work. When you say
(to_char(booking.bookdate,'dd-mon-yy'))=(to_char(bookDate,'dd-mon-yy'))
you presumably mean to compare the bookDate column in the booking table against the bookDate parameter. But since column names have precedence over local variables, the left-hand side of your expression is also looking at the bookDate column in the booking table. So you're comparing a column to itself. It would make much more sense to change the name of the parameter (to, say, p_bookDate) and then write
booking.bookDate = p_bookDate
or, if you want to do the comparison ignoring the time component of the dates
trunc( booking.bookDate ) = trunc( p_bookDate )

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