SQL Convert & Cast Nvarchar Time to a decimal - sql

I'm working on a legacy database and need to parse info from one database to another, parsing it into the new database is easy enough but first I need to create the query to convert and cast the following in the legacy SQL Server database:
WorkedHours(NVARCHAR(10)) is in text format 07:30
I need to convert and cast this as a decimal ie 7.5
I have searched around for the answer to this but can not find anything that has worked, so thought I would put it out there to see if any of you has any ideas.
Edit - What I should of asked is. What is causing an error converting to an int from a character with a value of 0 when trying to trying to convert and cast a time to a decimal?

DATEDIFF(
MINUTE,
0,
CAST('07:30' AS TIME)
)
/
60.0
Works up to '23:59' only
EDIT:
Based on a comment elsewhere, you have some 'bad' values.
This may find them...
SELECT
*
FROM
yourTable
WHERE
TRY_CONVERT(TIME, worked_hours) IS NULL
And as such, this is a safer version of my expression....
DATEDIFF(
MINUTE,
0,
TRY_CONVERT(TIME, worked_hours)
)
/
60.0
(Returns NULL for values that failed to parse.)

There's no reason to pull out the date/time types. Just do some simple string parsing:
cast(left(right('0' + WorkedHours, 5), 2) as int)
+ cast(right(WorkedHours, 2) as int) / 60.00
This won't have any limitations on 24 hours or anything like that. It just assumes that you've got one or two digits before a colon and two digits after.

This should work in SQL Server and an example-string "1101:56" (1101h & 56 minutes) | in general from 0h to >24h:
-- Take all hours before ":" and all Minutes (2 digits) after ":" and convert it to decimal.
select convert(decimal,left('1101:56',CHARINDEX(':','1101:56')-1)) + ( convert(decimal,right('1101:56',2))/60 );
-- with column-placeholder "time_str_from_table"
select convert(decimal,left(time_str_from_table,CHARINDEX(':',time_str_from_table)-1)) + ( convert(decimal,right(time_str_from_table,2))/60 );
If the source table have NULL-Values, than use "ISNULL" with substitution-value "0.0":
-- with column-placeholder "time_str_from_table"
select isnull( ( convert(decimal,left(time_str_from_table,CHARINDEX(':',time_str_from_table)-1)) + ( convert(decimal,right(time_str_from_table,2))/60) ), 0.0);

Related

Convert date to number data type

I am trying to convert date to number like below, not sure which function works better.
Database used is SQL Server.
Table details
create table test
(
id varchar(255),
call_date varchar(255)
);
insert into test('26203', '14-Aug-2020');
I need output as 4405726203 -- its concatenation of date (14-Aug-2014) + id (26203)
This is too long for a comment.
SQL Server allows you to convert a datetime to a float. That would be:
select cast(dte as float)
from (values (convert(datetime, '14-Aug-2020'))) v(dte)
However, the corresponding floating point value is 44055 (https://dbfiddle.uk/?rdbms=sqlserver_2019&fiddle=d142a64db0872e7572eb4fbd6d5d5fe7). It is a bit of mystery what your intention is.
You could subtract 2, but that seems arbitrary. You could calculate the number of days since 1899-12-30. But that also seems arbitrary.
In any case, once you figure out how to convert the date to the number you want, just use concat() to combine the values.
I have found the solution:
convert(varchar,CAST(CONVERT(datetime,call_date) as bigint)) + id
Under the hood, a SQL Server DateTime is a tuple of 2 32-bit integers:
The first integer is a count of days since since the epoch, which for SQL Server is 1 January 1900
The second integer is a count of milliseconds since start of day (00:00:00.000). Except that the count ticks up in 3- or 4-milliscond increments. Microsoft only knows why that decision was made.
You can get the count of days since the epoch with
convert( int, convert( date, t.call_date ) )
[wrap that in convert(varchar, ... ) to turn it into a string]
Looks like your id is already a varchar, so you can say:
select compound_key = convert(varchar,
convert(int,
convert(date,
call_date
)
)
)
+ t.id
from test t
I would suggest padding both fields with leading zeros to a fixed length so as to avoid possible collisions (assuming you're trying to generate a key here). Signed 32-bit integer overflows a 2.1 billion-ish, so 9 digits for each field is sufficient.
This works
select concat(datediff(d, 0, cast(call_date as date)), id)
from
(values ('26203','14-Aug-2020')) v(id, call_date);
Results
4405526203

SQL Server: convert and merge separate date and time columns (both integers)

I am working on a query, where I have to fill a table's column ([Result_DateTime]) with datetime values.
The datetime based on two columns, both integer. One contains the date and the other is the time, as it is.
As you can see from the picture, it is a bit difficult to merge and convert these values to an actual datetime, because of the way they are stored. Mainly the time value causing problems.
I concluded how to convert the date column:
CONVERT(DATETIME, LEFT(20200131, 8))
but then I got stuck - what to do with the time and how to merge the two into one datetime effectively?
Using function STUFF looks nasty...
Could you help me out please? I am using SQL Server 2014
Below is one method to do it:
SELECT CAST(Convert(DATE, LEFT(DATEUPDT, 8)) AS VARCHAR(10)) +' '+CAST (TIMEUPDT/100 AS VARCHAR(4)) + ':' + CAST(TIMEUPDT%(100 * (TIMEUPDT/100)) AS VARCHAR(10))+':00'
FROM TEST_TABLE_TIME;
I think I found one solution. What I tried is to avoid using varchar conversions because of how the time column's zeros are cut off. However, I am not convinced that this is the most effective way to do so:
DECLARE #DateInt int = 20200131
DECLARE #TimeInt int = 345 -- 03:45:00
SELECT CONVERT(DATETIME, LEFT(#DateInt, 8)) +
CAST(DATEADD(second, FLOOR(#TimeInt / 100) * 3600 + FLOOR(#TimeInt / 1) % 100 * 60, 0) as datetime)
I was testing it with various time values, it is working.

SQL date format from float (without a '1')

I have been given some data where there is a 'float' column that contains a date with a 1 in the front of it. I.e the value 1171030 represents 30th October 2017.
I am stuck in attempting to convert it to a normal date, when attempting to remove the one a dot appears (i.e. .171030).
Would really appreciate some guidance.
Many thanks
Yuck! Let's try datefromparts():
select datefromparts((val - 100000) / 10000, floor(val / 100) % 100, val % 100)
Or, here is another approach:
select convert(date, right(convert(varchar(255), cast(val as int)), 6))
SQL Server is actually pretty flexible in the date formats it understands.
I'm assuming this was probably produced by a non-Y2K compliant method such as JavaScript getYear() which simply returns current year minus 1900. It's not clear to me whether this data is coming from a flat file or it is already imported into a database table.
If you treat this value as a character string:
case length(val)
when 7 then cast('20' + right(val, 6) as date)
when 6 then cast('19' + val as date)
end
If you truly have a float (or int) value:
cast(cast(cast(19000000 + #val as int) as char(8)) as date)
In this case you'll need to convert through a character value rather than going straight to date. Be careful with string conversions from float to char. If you prefer shorter then you may be able to get away with this one:
cast(str(19000000 + #val, 8) as date);
You might get errors by assuming a length of 8 but that's probably a good way to catch and prevent problems.

convert Excel Date Serial Number to Regular Date

I got a column called DateOfBirth in my csv file with Excel Date Serial Number Date
Example:
36464
37104
35412
When i formatted cells in excel these are converted as
36464 => 1/11/1999
37104 => 1/08/2001
35412 => 13/12/1996
I need to do this transformation in SSIS or in SQL. How can this be achieved?
In SQL:
select dateadd(d,36464,'1899-12-30')
-- or thanks to rcdmk
select CAST(36464 - 2 as SmallDateTime)
In SSIS, see here
http://msdn.microsoft.com/en-us/library/ms141719.aspx
The marked answer is not working fine, please change the date to "1899-12-30" instead of "1899-12-31".
select dateadd(d,36464,'1899-12-30')
You can cast it to a SQL SMALLDATETIME:
CAST(36464 - 2 as SMALLDATETIME)
MS SQL Server counts its dates from 01/01/1900 and Excel from 12/30/1899 = 2 days less.
tldr:
select cast(#Input - 2e as datetime)
Explanation:
Excel stores datetimes as a floating point number that represents elapsed time since the beginning of the 20th century, and SQL Server can readily cast between floats and datetimes in the same manner. The difference between Excel and SQL server's conversion of this number to datetimes is 2 days (as of 1900-03-01, that is). Using a literal of 2e for this difference informs SQL Server to implicitly convert other datatypes to floats for very input-friendly and simple queries:
select
cast('43861.875433912' - 2e as datetime) as ExcelToSql, -- even varchar works!
cast(cast('2020-01-31 21:00:37.490' as datetime) + 2e as float) as SqlToExcel
-- Results:
-- ExcelToSql SqlToExcel
-- 2020-01-31 21:00:37.490 43861.875433912
this actually worked for me
dateadd(mi,CONVERT(numeric(17,5),41869.166666666664)*1440,'1899-12-30')
(minus 1 more day in the date)
referring to the negative commented post
SSIS Solution
The DT_DATE data type is implemented using an 8-byte floating-point number. Days are represented by whole number increments, starting with 30 December 1899, and midnight as time zero. Hour values are expressed as the absolute value of the fractional part of the number. However, a floating point value cannot represent all real values; therefore, there are limits on the range of dates that can be presented in DT_DATE. Read more
From the description above you can see that you can convert these values implicitly when mapping them to a DT_DATE Column after converting it to a 8-byte floating-point number DT_R8.
Use a derived column transformation to convert this column to 8-byte floating-point number:
(DT_R8)[dateColumn]
Then map it to a DT_DATE column
Or cast it twice:
(DT_DATE)(DT_R8)[dateColumn]
You can check my full answer here:
Is there a better way to parse [Integer].[Integer] style dates in SSIS?
Found this topic helpful so much so created a quick SQL UDF for it.
CREATE FUNCTION dbo.ConvertExcelSerialDateToSQL
(
#serial INT
)
RETURNS DATETIME
AS
BEGIN
DECLARE #dt AS DATETIME
SELECT #dt =
CASE
WHEN #serial is not null THEN CAST(#serial - 2 AS DATETIME)
ELSE NULL
END
RETURN #dt
END
GO
I had to take this to the next level because my Excel dates also had times, so I had values like this:
42039.46406 --> 02/04/2015 11:08 AM
42002.37709 --> 12/29/2014 09:03 AM
42032.61869 --> 01/28/2015 02:50 PM
(also, to complicate it a little more, my numeric value with decimal was saved as an NVARCHAR)
The SQL I used to make this conversion is:
SELECT DATEADD(SECOND, (
CONVERT(FLOAT, t.ColumnName) -
FLOOR(CONVERT(FLOAT, t.ColumnName))
) * 86400,
DATEADD(DAY, CONVERT(FLOAT, t.ColumnName), '1899-12-30')
)
In postgresql, you can use the following syntax:
SELECT ((DATE('1899-12-30') + INTERVAL '1 day' * FLOOR(38242.7711805556)) + (INTERVAL '1 sec' * (38242.7711805556 - FLOOR(38242.7711805556)) * 3600 * 24)) as date
In this case, 38242.7711805556 represents 2004-09-12 18:30:30 in excel format
In addition of #Nick.McDermaid answer I would like to post this solution, which convert not only the day but also the hours, minutes and seconds:
SELECT DATEADD(s, (42948.123 - FLOOR(42948.123))*3600*24, dateadd(d, FLOOR(42948.123),'1899-12-30'))
For example
42948.123 to 2017-08-01 02:57:07.000
42818.7166666667 to 2017-03-24 17:12:00.000
You can do this if you just need to display the date in a view:
CAST will be faster than CONVERT if you have a large amount of data, also remember to subtract (2) from the excel date:
CAST(CAST(CAST([Column_With_Date]-2 AS INT)AS smalldatetime) AS DATE)
If you need to update the column to show a date you can either update through a join (self join if necessary) or simply try the following:
You may not need to cast the excel date as INT but since the table I was working with was a varchar I had to do that manipulation first. I also did not want the "time" element so I needed to remove that element with the final cast as "date."
UPDATE [Table_with_Date]
SET [Column_With_Excel_Date] = CAST(CAST(CAST([Column_With_Excel_Date]-2 AS INT)AS smalldatetime) AS DATE)
If you are unsure of what you would like to do with this test and re-test! Make a copy of your table if you need. You can always create a view!
Google BigQuery solution
Standard SQL
Select Date, DATETIME_ADD(DATETIME(xy, xm, xd, 0, 0, 0), INTERVAL xonlyseconds SECOND) xaxsa
from (
Select Date, EXTRACT(YEAR FROM xonlydate) xy, EXTRACT(MONTH FROM xonlydate) xm, EXTRACT(DAY FROM xonlydate) xd, xonlyseconds
From (
Select Date
, DATE_ADD(DATE '1899-12-30', INTERVAL cast(FLOOR(cast(Date as FLOAT64)) as INT64) DAY ) xonlydate
, cast(FLOOR( ( cast(Date as FLOAT64) - cast(FLOOR( cast(Date as FLOAT64)) as INT64) ) * 86400 ) as INT64) xonlyseconds
FROM (Select '43168.682974537034' Date) -- 09.03.2018 16:23:28
) xx1
)
For those looking how to do this in excel (outside of formatting to a date field) you can do this by using the Text function https://exceljet.net/excel-functions/excel-text-function
i.e.
A1 = 132134
=Text(A1,"MM-DD-YYYY") will result in a date
This worked for me because sometimes the field was a numeric to get the time portion.
Command:
dateadd(mi,CONVERT(numeric(17,5),41869.166666666664)*1440,'1899-12-31')

SQL Server 2008: Varchar Conversion to Numeric Data Overflow, Probably Because Some Are Ranges

I'm working on a query with a varchar column called ALCOHOL_OZ_PER_WK. Part of the query includes:
where e.ALCOHOL_OZ_PER_WK >= 14
and get the errors:
Arithmetic overflow error converting varchar to data type numeric.
and:
Error converting data type varchar to numeric.
Looking into the values actually stored in the column, the largest look close to 100, but some of the entries are ranges:
9 - 12
1.5 - 2.5
I'd like to get the upper limit (or maybe the midpoint of the range) from rows with entries like this and have it be the value being compared to 14.
What would be the (or an) easy way to do this?
As always, thank you!
Your DB is obviously result of some survey, and it seems to contain the original survey data. The usual way is to run this through an ECCD (Extract, Clean, Conform, Deliver) process and store clean and standardized data into a separate database (maybe a warehouse) which can then be used for analytics and reporting.
If you have SSIS use data profiling task to get an idea of types of strings you have in there. The Column Pattern Profile reports a set of regular expressions on the string column, so you will get an idea of what's inside those strings. If you do not have SSIS, you can use eobjects DataCleaner to do the same.
If you can not spare a new database or at least a new table -- at minimum add a numeric column to this table and then extract numeric values form those strings into the new column. You may want to use "something else" (SSIS, Pentaho Kettle, Python, VB, C#) to do this -- in general T-SQL in not very good at string processing.
My guess is that this is not the only column that has garbage inside, so any analysis that you may run on this may be worthless.
And if you still think that the ranges are the only problem, this example may help:
First some data
DECLARE #myTable TABLE (
AlUnits varchar(10)
) ;
INSERT INTO #myTable
(AlUnits )
VALUES ( '10' )
, ( '15' )
, ( '20' )
, ( '7 - 12' )
, ( '3 - 5' )
;
The query splits records into two groups, numeric and not numeric -- assumed ranges.
;
WITH is_num
AS ( SELECT CAST(AlUnits AS decimal(6, 2)) AS Units_LO
,CAST(AlUnits AS decimal(6, 2)) AS Units_HI
FROM #myTable
WHERE ISNUMERIC(AlUnits) = 1
),
is_not_num
AS ( SELECT CAST( RTRIM(LTRIM(LEFT(AlUnits,
CHARINDEX('-', AlUnits) - 1)))
AS decimal(6,2)) AS Units_LO
,CAST(RTRIM(LTRIM(RIGHT(AlUnits,
LEN(AlUnits)
- CHARINDEX('-', AlUnits))))
AS decimal(6,2)) AS Units_HI
FROM #myTable
WHERE ISNUMERIC(AlUnits) = 0
)
SELECT Units_LO
,Units_HI
,CAST(( Units_LO + Units_HI ) / 2.0 AS decimal(6, 2)) AS Units_Avg
FROM is_num
UNION ALL
SELECT Units_LO
,Units_HI
,CAST(( Units_LO + Units_HI ) / 2.0 AS decimal(6, 2)) AS Units_Avg
FROM is_not_num ;
Returns:
Units_LO Units_HI Units_Avg
----------- ----------- ----------
10.00 10.00 10.00
15.00 15.00 15.00
20.00 20.00 20.00
7.00 12.00 9.50
3.00 5.00 4.00
Not sure about easy ways.
A proper way is to store the numbers in two columns, ALCOHOL_OZ_PER_WK_MIN and ALCOHOL_OZ_PER_WK_MAX.
As you say you need to calculate numeric values, which you can then use in your query.
Probably the easiest way is to use some simple logic to calculate the average or upper limit using string functions, and string to numeric functions.
If all you want is the upper limit, just get the characters after the '-' and use that.
"probably because some are ranges" - do you get that "range" is not a SQL Server Data type? You've got non-numeric data you're trying to convert into numeric data, and you've got a scalar value you're comparing to a non-scalar value.
This database has some issues.