SQL Decimal Field Conversion to Binary - sql-server

I have a question: in SQL Server there is a decimal data type.
I can convert this datatype to binary, so I can write query as
declare #deci decimal(18,2)
set #deci = 2.33
print cast(#deci as varbinary)
The result of this query is --
0x12020001E9000000
My question is what is the conversion rule for this conversion from decimal to binary..can anybody explain to me?

Related

T-SQL converting string into float

In a stored procedure on my SQL Server, I am trying to convert values from a varchar column into a float format.
The values into the varchar column are numbers with a sign at the beginning and a '.' before decimals.
Examples: '+0000000000000044.09' or '-0000000000114995.61'
If I try this: convert(float,mystring), it doesn't work.
I have:
Error converting data type varchar to float
Is this kind of conversion possible?
Or is there another way to convert a string with a sign and a '.' into a float?
As your examples both work, I'd guess there's another value somewhere in your table that's causing the problem. In recent versions of SQL Server (2012 onwards), the TRY_CONVERT function can be useful for tracking down this kind of issue.
TRY_CONVERT will not throw an exception on a conversion failure, but instead return a NULL value, so you can figure out which values are causing the problem like this:
SELECT * FROM your_table WHERE TRY_CONVERT(FLOAT, your_column_name) IS NULL
If any rows are returned, those are the rows with problem values that can't be converted to FLOAT.
You can try using CAST(mystring as float) or TRY_CONVERT(float,mystring).
Thuough convert(float,mystring) also should work fine. I would suggest checking your data.

How do I convert a varchar containing a number in scientific notation to a numeric in SQL Server?

I made some calculations using function and get the following value. I want to divide this value with 1000.
1.83673e+006
I want to convert the value into numeric.
When I try to convert it to numeric it throws
Error converting data type nvarchar to numeric.
Is it possible to convert this value to numeric? Please help me to get this.
Thanks in advance
try it
SELECT CONVERT(numeric(16,0), CAST(1.83673e+006 AS FLOAT))
In SQL Server, scientific notation (...+e...) is only used for floating-point data types, not for decimal/numeric data types.
Thus, SQL Server recognizes this format only when converting to a floating-point data type (such as float or real), not when converting directly to numeric.
Obviously, nothing prevents you from converting the value to float first and then to numeric:
SELECT CONVERT(numeric(19,4), CONVERT(float, '1.83673e+006'))
yields 1836730.0000.
Just try this
Declare #data varchar(100)='1.83673e+006'
SELECT #data=CAST(CAST( #data AS float) AS NUMERIC)/1000
SELECT #data Result
Result
1836.730000

SQL Server 2005 decimal field behaviour

Ive create a simple table with a field x of type decimal(28,15)
I run the following query to insert a value:
insert into testtable values (1234567890123)
when I do a select from testtable I, field x has a value of
1234567890123.000000000000000
Is there a way to specify (perhaps in the table design) that sql server should NOT store the zero's after the decimal if its not required? i.e. when doing a select the data will be returned as
1234567890123
Also why does insert into testtable values (12345678901234) give the following error :
Arithmetic overflow error converting numeric to data type numeric.
Also why does insert into testtable values (12345678901234) give the following error :
You specified a total width of 28 with 15 digits after decimal point. That leaves at most 13 digits before decimal point.
Is there a way to specify that sql server should NOT store the zero's after the decimal if its no required?
Strictly speaking, "decimal" is a fixed precision format and thus any number will occupy exactly the same space as any other number (see MSDN).
Try the below query . it works fine ...
select cast(1234567890123.000000000000000 as decimal)

Convert long decimal or float to varchar in SQL Server

One of the table I'm trying to query has a field with type decimal(38,19). I need to convert it to varchar in order for my perl DBI module to handle. How should I write the conversion in SQL to make it work? Specifically, if I run this in SQL Server Management Studio:
select convert(varchar, 19040220000.0000000000000000000)
I get:
Msg 8115, Level 16, State 5, Line 1
Arithmetic overflow error converting numeric to data type varchar.
I tried to round the number first:
select convert(varchar, round(19040220000.0000000000000000000, 0))
but that doesn't seem to work either (same error message). In fact round() doesn't seem to have an effect on that number for some reason. What should I do? Thx.
If you don't specify a length for your varchar, it defaults to 30 characters in the case of a CONVERT operation.
That's not long enough to hold your 38-digit decimal. So give your varchar an appropriate length in the CONVERT statement!!
Try this:
select convert(varchar(40), 19040220000.0000000000000000000)
You need to use a varchar with a set length larger than the precision you want, i.e.
select convert(varchar(64), 19040220000.0000000000000000000)

Problem convert column values from VARCHAR(n) to DECIMAL

I have a SQL Server 2000 database with a column of type VARCHAR(255). All the data is either NULL, or numeric data with up to two points of precision (e.g. '11.85'). I tried to run the following T-SQL query but received the error 'Error converting data type varchar to numeric'
SELECT CAST([MyColumn] AS DECIMAL)
FROM [MyTable];
I tried a more specific cast, which also failed.
SELECT CAST([MyColumn] AS DECIMAL(6,2))
FROM [MyTable];
I also tried the following to see if any data is non-numeric, and the only values returned were NULL.
SELECT ISNUMERIC([MyColumn]), [MyColumn]
FROM [MyTable]
WHERE ISNUMERIC([MyColumn]) = 0;
I tried to convert to other data types, such as FLOAT and MONEY, but only MONEY was successful. So I tried the following:
SELECT CAST(CAST([MyColumn] AS MONEY) AS DECIMAL)
FROM [MyTable];
...which worked just fine. Any ideas why the original query failed? Will there be a problem if I first convert to MONEY and then to DECIMAL?
Thanks!
It's likely that this depends on whether the decimal symbol is a comma or a dot. Here are some test queries and their results:
select CAST('3.6' as decimal) -- 3.60
select CAST('3,6' as decimal) -- Error converting data type varchar to numeric.
select CAST('3.6' as money) -- 3.60
select CAST('3,6' as money) -- 36.00 (!)
select ISNUMERIC('3.6') -- 1
select ISNUMERIC('3,6') -- 1
The documentation for ISNUMERIC says :
ISNUMERIC returns 1 when the input
expression evaluates to a valid
integer, floating point number, money
or decimal type; otherwise it returns
0
Both 3.6 and 3,6 can be cast to money, so that's why isnumeric('3,6') returns 1.
To resolve this issue, replace the comma's with dots (or vice versa, if your system uses comma as the decimal symbol):
select cast(replace('3,6',',','.') as decimal)
Another option is to change the "decimal symbol" in Windows. It's in Config Panel -> Regional and Language -> Formats -> Additional Settings -> Numbers.
Another cause is empty strings. For example, if you use the import wizard to import a CSV file, empty fields will become empty strings, not nulls.
This is a common idiom for fixing this:
CAST(NULLIF([number_as_a_string],'') AS decimal(13,2))
Select CAST(isnull(MyColumn,0) as Decimal(4,2))
FROM [MyTable];

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