What is the correct way to specify the format of a datetime2 field when creating a table in Azure SQL data warehouse? I don't seem to be able to find an example in the documentation.
The data looks like this:
"2020-09-14T20:50:48.000Z"
CREATE TABLE [Foo].[Bar](
...
MyDateTime datetime2(['YYYY-MM-DDThh:mm:ss[.fractional seconds]')
)
As Panagiotis notes, the underlying representation is an int/long for the actual date value. This is how RDBMS engines can quickly compute the delta between two dates (days between Monday and Friday is a simple subtraction problem). To answer your question, you simply would format your create table as:
CREATE TABLE [Foo].[Bar](
...
MyDateTime datetime2
)
If you're interested in formatting the result in a query, you can look to the CONVERT or FORMAT functions. For example, if you wanted the format dd-mm-yyyy (Italian date), you could use either of the following:
SELECT
CONVERT(VARCHAR, CURRENT_TIMESTAMP, 105)
, FORMAT(CURRENT_TIMESTAMP, 'dd-MM-yyyy')
Note: CONVERT is generally faster than FORMAT and is the recommended approach if you have a date format that is supported. This is because the FORMAT function relies on the CLR which will include a context/process jump.
Related
I only need to take the time part from the 'Timestamp type source attribute' and load it into a dedicated SQL pool table (Time datatype column). But I don't find a time function within the expression builder in ADF, is there a way I can do it?
-What did I do?
-I took the time part from the source attribute using substring and then tried to load the same into the destination table, when I do the destination table inserted null values as the column at the destination table is set to time datatype.
I tried to reproduce this and got the same issue. The following is a demonstration of the same. I have a table called mydemo as shown below.
CREATE TABLE [dbo].[mydemo]
(
id int NOT NULL,
my_date date,
my_time time
)
WITH
(
DISTRIBUTION = HASH (id),
CLUSTERED COLUMNSTORE INDEX
)
GO
The following is my source data in my dataflow.
time is not a recognized datatype in azure dataflow (date and timestamp are accepted). Therefore, dataflow fails to convert string (substring(<timestamp_col>,12,5)) into time type.
For better understanding, you can load your sink table as source in dataflow. The time column will be read as 1900-01-01 12:34:56 when time value in the table row is 12:34:56.
#my table row
insert into mydemo values(200,'2022-08-18','12:34:56')
So, instead of using substring(<timestamp_col>,12,5) to return 00:01, use concat('1900-01-01 ',substring(<timestamp_col>,12,8)) which returns 1900-01-01 00:01:00.
Configure the sink, mapping and look at the resulting data in data preview. Now, azure dataflow will be able to successfully insert the values and give desired results.
The following is the output after successful insertion of record into dedicated pool table.
NOTE: You can construct valid yyyy-MM-dd hh:mm:ss as a value using concat('yyyy-MM-dd ',substring(<timestamp_col>,12,8)) in place of 1900-01-01 hh:mm:ss in derived column transformation.
I have column ABC where timestamp is of format dd/MM/yyyy HH:mm:SS (11/04/2020 1:17:40).I want to create another column ABC_NEW with same data as old column but with different timestamp 'yyyy-MM-dd HH:mm:SS'.I tried doing in azure data factory derived column using
toTimestamp(column_name,'yyyy-MM-dd HH:mm:SS') but it did not work it is coming as NULL. Can anyone help?
It's a 2-step process. You first need to tell ADF what each field in your timestamp column represents, then you can use string conversions to manipulate that timestamp into the output string as you like:
toString(toTimestamp('11/04/2020 1:17:40','MM/dd/yyyy HH:mm:ss'),'yyyy-MM-dd HH:mm:SS')
Data Factory doesn't support date format 'dd/mm/yyyy', we can not convert it to 'YYYY-MM-DD' directly.
I use DerivedColumn to generate a new column ABC_NEW from origin column DateTime and enter the expression bellow：
toTimestamp(concat(split(substring(DateTime,1, 10), '/')[3], '-',split(substring(DateTime,1, 10), '/')[2],'-',split(substring(DateTime,1, 10), '/')[1],substring(DateTime,11, length(DateTime))))
The result shows:
This is a trick which was a blocker for me, but try this-
Go to sink
Mapping
Click on output format
Select the data format or time format you prefer to store the data into the sink.
I have a timestamp in ISO-8601 format and want to specify it either as a timestamp or datetime format when creating a table in Athena. Any clues on how to do this ?
Thanks!
When you create table in Athena you can set a column as date or timestamp only in the Unix format as follows:
DATE, in the UNIX format, such as YYYY-MM-DD.
TIMESTAMP. Instant in time and date in the UNiX format, such as
yyyy-mm-dd hh:mm:ss[.f...]. For example, TIMESTAMP '2008-09-15
03:04:05.324'. This format uses the session time zone.
If the format is different, define it as a String and when you query the data use the date function:
from_iso8601_date(string) → date
You can convert the data to make it easier and cheaper for specific use cases by using CTAS (create table as select) query that will generate a new copy of the data in a simpler and more efficient (compressed and columnar) parquet format.
I am usig azure data factory and basically I need to add a dynamic content (date function) to do this:
SELECT DATEADD(DAY, -2, GETDATE())
any idea?
I guess you can do the below using Logical Function
#equals(formatDateTime(addDays(utcnow(),-2),'yyyy-MM-dd'),formatDateTime(activity('Your Metadata Activity Name').output.lastmodifieddate,'yyyy-MM-dd'))
You can use just addDays() function to get date differences. Detailed document on Azure Data Factory expressions and function is available : here
I used #{formatDateTime(convertfromutc(addDays(utcNow(),-6),'Eastern Standard Time'), 'yyyy-MM-dd' )} Here I wanted to get 6 days old date (from current date).
If Date contains timestamp then you should try below code.
#string(addhours('2022-08-03 06:20:51',-2, 'yyyy-MM-dd HH:mm'))
In plain SQL (in my case: sqlite), I would be able to query for a specific date in a DATE column as follows:
SELECT * FROM table WHERE date(dateColumn) = '2015-01-01'
This works because the date() function cuts off the time part of the DATE value.
Can I do something similar with Predicates in Core Data? Or do I have to use something where I determine the start and end of that day and then look for dates between the two date values?