This code works great:
select month(period)
from fmdr3.dbo.fmdr_2017
It returns the number of the month from a date column.
I'm trying to figure out how to insert the results into the table FMDR_2017 in a column called Month.
I've been trying permutations of this:
insert into fmdr3.dbo.fmdr_2017(Month)
select month(period)
from fmdr3.dbo.fmdr_2017
but haven't had any success yet.
Thank you.
I'm guessing you'll want to update the Month column based on the period?
UPDATE fmdr3.dbo.fmdr_2017
SET Month = Month(Period);
It sounds like you're trying to update a value in existing records, is that right?
If so, you need something like this:
UPDATE fmdr3.dbo.fmdr_2017
SET [Month] = month(period)
see http://sqlfiddle.com/#!6/7c403/1
Related
Lets say i have a small db table with only two fields. (MSSQL) Like this:
date (Date) daily_counter (Int)
-------------------------
2021-07-18 0
2021-07-18 1
2021-07-18 2
2021-07-19 0
I want to insert a new fifth row and insert value "2021-07-19" to the date field. And i want to know what the daily_counter is for my new row.
As you perhaps understand by the example, the daily_counter is supposed to auto increase, starting over each day.
So, since there is already a row with that date with the value 0 on the field daily_counter. I want to add 1 to daily_counter for my new row without sending the value 1 to the query.
How can i think when designing this type of table and data. Any hints appreciated. Thanks!
Kr
Gustav
UPDATE:
Ok, i think i got something that could work. The only downside would be when deleting and adding new rows, as the new id could be previosly used and deleted and added again.
A side from that i think i got something that i can use.
It might not be pretty now, but it looks like this.
It seems to work also when there is no row for the current day.
DECLARE #date DATE
SET #date = '2021-07-22'
DECLARE #daily_counter INT
SET #daily_counter = (SELECT MAX(daily_counter) from mytable where date = #date);
SET #daily_counter = #daily_counter + 1;
IF #daily_counter IS NULL
BEGIN
SET #daily_counter = 1;
END
INSERT INTO
mytable
(date, daily_counter)
OUTPUT #daily_counter
VALUES (#date, #daily_counter)
Thanks again for the help!
It's not possible to make the database do this automatically in the row itself. You must have a single counter across all dates (a SEQUENCE would be good for this).
What you can do is use the row_number() function to simulate this at the point where you query the data:
SELECT *, row_number() over (partition by [date] order by [date])
FROM ...
Unfortunately, this will still fail if you need to preserve the original position following deletes, but there's not a good way to do this right now in a database without triggers or application code.
I have a table in Teradata ABC_XXX where XXX will change monthly basis.
For Ex: ABC_1902, ABC_1812, ABC_1904 etc...
I need to access this table in my application without modifying the code every month.
Is that any way to do in Teradata or any alternate solution.??
Please help
Can you try using DBC.TABLES in subquery like below:
with tbl as (select 'select * from ' || databasename||'.'||tablename as tb from
dbc.tables where tablename like 'ABC_%')
select * from tbl;
If you can get the final query executed in your application, you will be able to query the required table without editing the query.
The above solution is with expectation that the previous month's table gets dropped whenever a new month's table is created.
However, if previous table is not being dropped, then you can try the below approach:
select 'select * from db.ABC_' ||to_char(current_date,'YYMM')
Output will be
select * from db.ABC_1902
execute the output in your application, you will be able to query dynamic table.
I am using the latest SQL Server. I have a table with a CreatedDate column. I need to write a Query that uses dates that are plus or minus 7 from the Date in CreatedDate. I have no clue how to go about this. My thought was this:
DECLARE #Date datetime
DECLARE #SevenBefore datetime
DECLARE #SevenAfter datetime
SET #Date = CreatedDate
SET #SevenBefore = DATEADD(day,-7,#Date)
SET #SevenAfter = DATEADD(day,7,#Date)
SELECT *
FROM <table>
WHERE <table> BETWEEN #SevenBefore AND #SevenAfter
The issue with this is that I cannot use "CreatedDate" as a SET #DATE because SQL gives an error "Invalid column name 'CreatedDate'"
Any help would be appreciated. I cannot list a date because every date in that column could be different.
Thanks
In this case, you need to stop thinking as a programmer would, and start thinking as a Database programmer would.
Lets work only with this central part of your query:
SELECT *
FROM <table>
WHERE <table> BETWEEN #SevenBefore AND #SevenAfter
Now, you say that the CreatedDate is a column in a table. For this example, I will assume that the CreatedDate is in a table other than the one in your example above. For this purpose, I will give two fake names to the tables. The table with the CreatedDate, I will call tblCreated, and the one from the query above I will call tblData.
Looking above, it's pretty obvious that you can't compare an entire table row to a date. There must be a field in that table that contains a date/time value. I will call this column TargetDate.
Given these assumptions, your query would look something like:
SELECT *
FROM tblCreated tc
INNER JOIN tblData td
ON td.TargetDate BETWEEN DATEADD(day, -7, tc.CreatedDate) and DATEADD(day, 7, tc.CreatedDate)
Looking at this, it is clear that you still need some other associations between the tables. Do you only want all data rows per customer based on the Created date, or perhaps only want Creations where some work was done on them as shown in the Data records, or ??. Without a fuller specification, we can't help with that, though.
I need a column to be dynamic as such that a column DaysToExpiration is calculated based on the number of days between now and a date column Expiration Date.
My plan was to add a trigger that fires on a SELECTstatement of the table.
Is this possible? How?
Is there a better way to go about this?
You say "My plan was to add a Trigger that Fires on a SELECT statement of the table."
In that case why have a column at all, why not just select it in your final query?
Select DateDiff(day,getdate(),ExpirationDate) AS [DaysToExpiration]
If it must be persisted and stored in a column then you can make it a computed column as suggested in the comments. Or you could have the table trigger on UPDATE/INSERT so when the ExpirationDate is inserted or updated it sets the DaysToExpiration column to the result of the provided code.
No there is no provision of having trigger on SELECT operation. You can use stored procedure which takes parameters that are fetched from SELECT query and call this procedure after desired SELECT query.
Using SQL Server 2005
When i insert the date it should compare the date in the table.
If it is equal with other date, it should display a error message and also it should allow only to insert the next date.
For Example
Table1
Date
20091201
20091202
Insert into table1 values('20091202')
The above query should not allow to insert the same value
Insert into table1 values('20091204')
The above query also should not allow to insert the long gap date.
The query should allow only the next date.
It should not allow same date and long gap date.
How to insert a query with this condition.
Is Possible in SQL or VB.Net
Need SQL Query or VB.Net code Help
You could use a where clause to ensure that the previous day is present in the table, and the current day is not:
insert into table1 ([dateColumn])
select '20091204'
where exists (
select * from table1 where [dateColumn] = dateadd(d,-1,'20091204')
)
and not exists (
select * from table1 where [dateColumn] = '20091204'
)
if ##rowcount <> 1
raiserror ('Oops', 16, 1)
If the insert succeeds, ##rowcount will be set to 1. Otherwise, an error is returned to VB using raiserror.
Why not just have a table of dates set up in advance, and update a row once you want to "insert" that date?
I'm not sure I understand the point of inserting a new date only once, and never allowing a gap. Could you describe your business problem in a little more detail?
Of course you could use an IDENTITY column, and then have a computed column or a view that calculates the date from the number of days since (some date). But IDENTITY columns do not guarantee contiguity, nor do they even guarantee uniqueness on their own (unless you set up suc a constraint separately).
Preventing duplicates should be done at the table level with a unique constraint, not with a query. You can check for duplicates first so that you can handle errors in your own way (rather than let the engine raise an exception for you), but that shouldn't be your only check.
Sounds like your date field should just be unique with auto-increment.