Invalid datetime string when CAST As Date - sql

I have Time column in BigQuery, the values of which look like this: 2020-09-01-07:53:19 it is a STRING format. I need to extract just the date. Desired output: 2020-09-01.
My query:
SELECT
CAST(a.Time AS date) as Date
from `table_a`
The error message is: Invalid datetime string "2020-09-02-02:17:49"

You could also use the parse_datetime(), then convert to a date.
with temp as (select '2020-09-02-02:17:49' as Time)
select
date(parse_datetime('%Y-%m-%d-%T',Time)) as new_date
from temp

How about just taking the left-most 10 characters?
select substr(a.time, 1, 10)
If you want this as a date, then:
select parse_date('%Y-%m-%d', substr(a.time, 1, 10))

select STR_TO_DATE('2020-09-08 00:58:09','%Y-%m-%d') from DUAL;
or to be more specific as your column do as:
select STR_TO_DATE(a.Time,'%Y-%m-%d') from `table_a`;
Note: this format is applicable where mysql is supported

Related

Date column which contains null values as well

i have column called startup_date which defined as STRING datatype in bigquery
which contains value like "2001-09-09 02:19:38.0 UTC" and null values as well
please help to use convert function to fetch only date value not hours and mins
used below function and getting invalid datetime string error message
EXTRACT(date FROM
datetime(CASE when startup_date = '' THEN NULL ELSE startup_date END))
The DATE and TIMESTAMP functions do exactly what you are looking for. If you have a STRING column where its format is like TIMESTAMP, you can simply apply it. Then, DATE will extract just the date and it takes care of the NULL values.
WITH my_data AS
(
SELECT TIMESTAMP("2001-09-09 02:19:38.0 UTC") AS startup_date UNION ALL
SELECT NULL UNION ALL
SELECT "2021-10-10 07:29:30.0 UTC"
)
SELECT DATE(startup_date) as date FROM my_data
returns:
You can try substr[1] from 1 to 10 to get the date, and then you can use the safe.parse_date function[2].
SELECT safe.parse_date('%Y-%m-%d', substr(startup_date, 1, 10)) AS startup_date FROM you_dataset.your_table
It returns this:
[1] https://cloud.google.com/bigquery/docs/reference/standard-sql/string_functions#substr
[2] https://cloud.google.com/bigquery/docs/reference/standard-sql/functions-and-operators#parse_date

Converting String to Date in BigQuery?

I have a timestamp in my big query looking like this: 30/01/2020 00:14:05
date is one of the column names of the table
I have already tried:
1. cast(PARSE_DATE('%Y%m%d', date) as DATE)
2. CAST(date as DATE)
In your case you need SELECT PARSE_DATETIME('%d/%m/%Y %H:%M:%S','30/01/2020 00:14:05')
or SELECT PARSE_DATE('%d/%m/%Y',SUBSTR('30/01/2020 00:14:05',1,10)) if you only need the date

SQL: How To Select Earliest Date

I have a date column & I am simply trying to know the earliest date. I use the command:
select Min(Install_date) From PocketGemsSchema.pocketgemstable2;
This returns 1-Dec-17
But the minimum date from my sample data is actually 1-Nov-17.
Can anyone help please?
Try this:
If your Install_date contain datatype varchar than
SELECT MIN(CAST(Install_date AS DATE))
FROM PocketGemsSchema.pocketgemstable2
SELECT FORMAT(MIN(CAST(Install_dateAS DATE)), 'dd-MMM-yy ')
FROM PocketGemsSchema.pocketgemstable2
If your Install_date contain datatype date or datetime than your query will work
I think its the data type issue , you can try two approach
convert the field to datatime and your query should work
cast it on the run time like below
Mysql
SELECT Min(Str_to_date(Install_date, '%m/%d/%Y'))
FROM pocketgemsschema.pocketgemstable2;
SQL server
SELECT Min(Cast(Install_date as datetime))
FROM pocketgemsschema.pocketgemstable2;
I would change the column to a date or a datetime type and sort out any bugs that arise.

Convert/get varchar variable to YYYYMM

I have 4 CTE's in this table and the third one contains a DATETIME converted to VARCHAR (with format based on the requirement) as startDate in DD/MM/YYYY format. The last cte does calculations based on the data generated and one of the columns needs to store YYYYMM date based on startDate.
The problem it's getting the year and the month from this converted DATETIME, using convert() it shows this:
IDPER
-------
01/01/ --DD/MM/
These 2 show YYYYMM correctly when startDate isn't converted:
Select *, left(convert(nvarchar(6),new_ini,112),6) as IDPER from table
Select *, convert(nvarchar(6),new_ini,112) as IDPER from table
How could I get YYYYMM format having startDate converted? Or what could be a more smart approach to the requirement
If you have a string in the format DD/MM/YYYY and you want YYYYMM, then use string operations:
select right(new_ini, 4) + substring(new_ini, 4, 2)
You should be storing date values as dates or a related type, not as string. But given that you have already stored this as a string, string operations can do what you need.
My way would be slightly different
SELECT CONVERT(NVARCHAR(6), CONVERT(DATE, new_ini, 103), 112);
Here, I first converted it to date and then formatted to YYYYMMDD and taken 6 chars only
declare #date DATE = GETDATE();
select REPLACE(LEFT(CONVERT(DATE,#date,112),8),'-','') -- 1st approach
select FORMAT(#date,'yyyyMM') --2nd approach

query to search dates which are stored as string in the database

I have a table where I store an activity completion date as varchar. The format of the date stored is MM/DD/YYYY HH:MM:SS.
I have search window where I have two fields Completion date from and completion date to.The date format selected here is MM/DD/YYYY.
How do I write a query such that I am able to fetch the activity completion between two given dates from the table which has the dates stores as varchar.This table was created a long time back and no thought was given to saving dates as datetime.
You can use SQL CONVERT to change your columns to DATE format but that will cause performance issues.
SELECT *
FROM MyTable
WHERE CONVERT(DATETIME, MyDate) >= CONVERT(DATE, '01/01/2014')
AND CONVERT(DATETIME, MyDate) <= CONVERT(DATE, '01/31/2014')
CONVERT documentation - http://msdn.microsoft.com/en-us/library/ms187928.aspx
if you are unable to change how data is stored, than for better performance , you can create view with calculated column that converts VARCHAR to DATETIME. After that can create index on calculated column. Index on Computed Column documentation
Use the SUBSTRING function to get the date parts in a comparable order (i.e. yyyymmdd):
select *
from mytable
where
CONCAT( SUBSTRING(thedate, 7, 4) , SUBSTRING(thedate, 4, 2) , SUBSTRING(thedate, 1, 2) )
between
CONCAT( SUBSTRING(#FROMDATE, 7, 4) , SUBSTRING(#FROMDATE, 4, 2) , SUBSTRING(#FROMDATE, 1, 2) )
and
CONCAT( SUBSTRING(#TODATE, 7, 4) , SUBSTRING(#TODATE, 4, 2) , SUBSTRING(#TODATE, 1, 2) )
;
You could use this code :
select * from table_name
where CAST(col1 as date )
between CAST(Completion date from as date )
and CAST(Completion date to as date);
Function syntax CAST:
CAST ( expression AS data_type )
You can use below if the date format is {yyyy-MM-dd}, or you can adjust the charindex's index value depending on format
SELECT *
FROM table
WHERE
CHARINDEX('-', col_value, 0) = 5
AND CHARINDEX('-', col_value, 6) = 8
AND LEN(col_value) = 10
The above piece will look for first occurrence of char '-' at position 5 and the second char '-' at position 8 while the entire date value's length is equal to 10 chars
This is not full proof, but will narrow down the search. If you want to add time then just expand the criteria in the where to accommodate the format i.e. {yyyy-MM-dd 00:00:00.000}
This is a safe way to query the data, without any unexpected 'invalid cast / convert' errors.