"Date" data from GA in BQ is "yyyymmdd" which is not able to convert to "date" data set.
Is there any way to make BQ recognize it as "date"?
Thank you,
According to the documentation, the date field is exported as String from your GA data.
However, it is possible to change that after you export your data to BigQuery. You can overwrite your current table or create a new one with the date format you desire. In order to achieve this, we will use PARSE_DATE() builtin method. It receives a String that will be casted to date according to the string format it has. Below is the StandardSQL syntax in BigQuery:
SELECT PARSE_DATE("%Y%m%d", date) as date FROM `project.dataset.table`
The date will be outputed as YYYY-MM-DD. In addition, if you want to change the date format, you can use FORMAT_DATE() builtin method using one of the formatting elements.
In your case that you want to replace the whole table with the date column with the desired format, you could use the following syntax:
CREATE OR REPLACE TABLE `project.dataset.table` AS
( SELECT * REPLACE(PARSE_DATE("%Y%m%d",date) as date) FROM `project.dataset.table`)
Therefore, your table will have all the same columns, but the date field will be formatted as DATE.
Related
I am reading a file from ADLS location, in that one column Period_Ending_Date is having data type as STRING.
The Period_Ending_Date is having many dates in random order, I need to apply filter to get the latest date.
I'm trying this code:
select * from final_table
WHERE Period_Ending_Date = (SELECT MAX(Period_Ending_Date) FROM final_table)
But the problem is I'm getting the day with maximum, not the latest date. I can understand this is happening because of STRING data type. Please guide me how I can change this column to DATE data type or any other alternative to get the solution of this.
I'm working with Scala and SQL on Azure Databricks.
what about changing SELECT MAX(Period_Ending_Date) FROM final_table to SELECT MAX(cast(Period_Ending_Date as date)) FROM final_table - performing explicit casting to date if date format is ISO8601 (YYYY-MM-DD) or using the to_date function (doc) to convert non-standard dates.
I need to store a date on MM/YYYY format (without the day) on PostgreSQL.
Is that possible?
I don't want to just pick a day and store the day as well because that would be an incorrect information.
thanks.
mm/yyyy is not a valid date. The day is part of it, and cannot be removed. One alternative would to store the data in a string datatype instead of date, but I would not recommend that: doing so exposes you to data integrity issues (something like 13/2010, for example, is not a valid date part).
For this reason, I would still recommend using the date datatype. You can just ignore the day when accessing the data, if that's not relevant for you. You can also create a computed column based on the date, that displays the information in the format you want:
create table mytabnle (
...
mydate date,
mystr text geneated always as (to_char(mydate, 'mm/yyyy')) stored
);
I need help in figuring out the date conversion logic in Snowflake. The documentation isn't clear enough on this.
In SQL Server, I would try
SELECT CONVERT(DATE, '20200730', 101)
and it gives me '07/30/2020'.
If I try the following in Snowflake,
to_varchar('20200730'::date, 'mm/dd/yyyy')
it gives me '08/22/1970'. Why would it give an entire different date? Need help in getting the logic with the correct date.
The issue with what you are doing is that you are assuming that Snowflake is converting your string of '20200730'::DATE to 2020-07-03. It's not. You need to specify your input format of a date. So, 2 options based on your question being a bit vague:
If you have a string in a table and you wish to transform that into a date and then present it back as a formatted string:
SELECT TO_VARCHAR(TO_DATE('20200730','YYYYMMDD'),'MM/DD/YYYY');
--07/30/2020
If the field in the table is already a date, then you just need to apply the TO_VARCHAR() piece directly against that field.
Unlike SQL Server, Snowflake stores date fields in the same format regardless of what you provide it. You need to use the TO_VARCHAR in order to format that date in a different way...or ALTER SESSION SET DATE_OUTPUT_FORMAT will also work.
Try select to_varchar(TO_DATE( '20200730', 'YYYYMMDD' ), 'MM/DD/YYYY'); which produces 2020-07-30
You may need to refer to https://docs.snowflake.com/en/user-guide/date-time-input-output.html#timestamp-formats
I am confused with to_date(char[,'format'[,nls_lang]) function. Lets suppose I have to_date('31-DEC-1982','DD-MON-YYYY');should the format specified in the function be same as the date string? The above function works fine. When I use to_date('31-DEC-1982','DD-MM-YYYY'); also works fine but the month field in date string and that in format does not match.
So my doubt is should the date string and format specified match exactly to convert it to Date object.
Thanks
Generally speaking, yes, the date string and specified format should match. But the reason why it works in your case is that Oracle, for certain cases, provides flexibility of alternative format matching.
Excerpt from official Oracle Site
If a match fails between a datetime format element and the corresponding characters in the date string, then Oracle attempts alternative format elements
So as per above table, you can use 'MON' or 'MONTH' in place of 'MM'.
Similarly you can use 'YYYY' in place 'YY', etc
Reference:
Oracle Format Matching
Whatever format you follow, the object returned will be of date type.
You can test this via creating a dummy table and showing the table description.
e.g. CREATE TABLE TEST AS(
select to_date('31-DEC-1982','DD-MON-YYYY') dd from dual);
Now desc test;
Result will be dd date.
Similar will be the result with another type.
However if you are using SQL Developer, the date will be show in the exact NLS format as the setting there applies.
tools->preferences->database->NLS
I want to create a table in Oracle 10g and I want to specify the date format for my date column. If I use the below syntax:
create table datetest(
........
startdate date);
Then the date column will accept the date format DD-MON-YY which I dont want.
I want the syntax for my date column to be MM-DD-YYYY
Please let me know how to proceed with this.
Regards,
A DATE has no inherent format. It is not simply a string that happens to represent a date. Oracle has its own internal format for storing date values.
Formats come into play when actual date values need to be converted into strings or vice versa, which of course happens a lot since interactively we write dates out as strings.
The default date format for your database is determined by the settings NLS_DATE_FORMAT, which you probably have set to DD-MON-YYYY (which I believe is the default setting for American English locales). You can change this at the database level or for a single session for convenience, but in general it is safer programming practice to be explicit so that you don't get errors or, worse, wrong results if your code is run in a different environment.
The simplest way to specify a date value unambiguously is a date literal, which is the word 'date' followed by a string representing the date in YYYY-MM-DD format, e.g. date '2012-11-13'. The Oracle parser directly translates this into the corresponding internal date value.
If you want to use a different format, then I recommend explicitly using TO_CHAR/TO_DATE with your desired format model in your code. Examples:
INSERT INTO my_table (my_date) VALUES ( TO_DATE( '11-13-2012', 'MM-DD-YYYY' ) );
SELECT TO_CHAR( my_date, 'MM-DD-YYYY' ) FROM my_table;
dates rdo not have a format like you're suggesting. they are stored internally as a 7 byte number. to format the date when selecting, please use TO_CHAR(yourdatefield, 'format')
where formats are all shown here: http://docs.oracle.com/cd/B19306_01/server.102/b14200/sql_elements004.htm#i34924
eg to_char(startdate, 'mm-dd-yyyy')