I am running the following code to get the length of a value before the decimal place:
SELECT LEN(FLOOR(CAST([VALUE] AS FLOAT))) FROM TABLE1 WHERE VALUE2 <> 'B'
The [VALUE] column in TABLE1 is of type nvarchar(30) hence the cast. The column also contains some non-numeric values but these are filtered out by the WHERE clause as they all have a 'B' value for VALUE2.
The code works as expected and returns '6' for values with 6 digits such as '123456.123'. It also works correctly for values with less than 6 digits. However, the code simply returns '12' for any value with greater than 6 digits such as '12345678'.
I've done some googling and can't seem to find a reason for this? Any explanations / alterations / alternatives would be much appreciated!
LENGTH() function expects string expression, so the float value is implicitly converted to string using scientific notation. The following statement demonstrates this issue and the unexpected result:
SELECT
LEN(FLOOR(CAST([VALUE] AS FLOAT))),
FLOOR(CAST([VALUE] AS FLOAT)),
CONVERT(varchar(50), FLOOR(CAST([VALUE] AS FLOAT)))
FROM (VALUES
(N'12345678')
) TABLE1 ([VALUE])
Result:
12 12345678 1.23457e+007
A possible solution, without using an integer (and/or float) conversion, is the following statement:
SELECT CHARINDEX(N'.', CONCAT([VALUE], N'.')) - 1
FROM (VALUES
(NULL),
(N'12345678'),
(N'123456.123'),
(N'99999.923')
) TABLE1 ([VALUE])
I am running the following code to get the length of a value before the decimal place:
This value is called the log base 10 plus 1 -- at least for numbers greater than 1. So how about using:
floor(log10(value)) + 1
You can tweak this for values less than 1 (including negative values) if that is needed.
Case A: When you are trying to round the result yourself to the nearest decimal
SELECT ROUND (3.833333333333333) -- 4
Case B: When you let SQL do the math and then round to the nearest decimal
SELECT ROUND (23/6) -- 3 (OR CEIL)
In this case according to the order of operations:
SQL will divide what’s between the parenthesis, first = 3.833333333333333
And then (This is the problem) it will erase everything in the decimal places. (Converting it to int, automatically) =3.0
Now, let's round the decimals (Which are already erased in the previous step! And now it’s = 0)
So, the last result will be (3). Not (4).!
Even with conversions:
SELECT CAST (DIV (23,6) AS NUMERIC (10,5)) AS tst -- 3.00000
SELECT CAST ((23/6) AS DECIMAL (5,2)) AS tst -- 3.00
SELECT CAST (23/6 AS FLOAT) AS tst -- 3
SELECT CAST (23/6 AS REAL) AS tst -- 3
Is there a solution to this problem ?
Because it performs integer division. When then engine evaluates:
ROUND (23/6)
the expression 23/6 is evaluated first as 3. Then:
ROUND (3)
is evaluated as 3.
If you want the float precision you can multiply by 1.0. For example by doing:
ROUND ( 1.0 * 23/6)
Objective:
I have a column 'amount' with decimals. I am trying to exclude rows where the amount value ends either with '0's or '5's.
How can I achieve that...
Column type: decimal (7,2)
Ex: numbers to exclude
10.25
11.20
100.00
You probably want this:
WHERE (CAST(your_field * 100 AS INTEGER) % 5) <> 0
But it is hard to tell without more detail on your data type. Also there can be funky rounding issues with floating point values.
An interesting way to do this uses "modular" arithmetic
where col % 0.1 not in (0.00, 0.05)
The % operator works on non-integer bases as well as integer ones.
What I did here is changed the number into a string, trimmed off the trailing blanks, and then reversed the string to take the first character to see if it was no 1 or 5
SELECT * into #test FROM (SELECT CAST(10.25 as decimal(7,2)) as val UNION SELECT 8.21 UNION SELECT 6.00) DQ
select * from #test WHERE LEFT(REVERSE(RTRIM(CAST(val as nvarchar(50)))),1) NOT IN ('5', '0')
drop table #test
This post has the following code:
DECLARE #A DECIMAL(3, 0), #B DECIMAL(18, 0), #F FLOAT
SET #A = 3
SET #B = 3
SET #F = 3
SELECT 1 / #A * 3.0, 1 / #B * 3.0, 1 / #F * 3.0
SELECT 1 / #A * 3 , 1 / #B * 3 , 1 / #F * 3
Using float, the expression evaluates to 1. Using Decimal, the expression evaluates to some collection of 9s after the decimal point. Why does float yield the more accurate answer in this case? I thought that Decimal is more accurate / exact per Difference between numeric, float and decimal in SQL Server and Use Float or Decimal for Accounting Application Dollar Amount?
The decimal values that you have declared are fixed width, and there are no points after the decimal place. This affects the calculations.
SQL Server has a rather complex formula for how to calculate the precision of arithmetical expressions containing decimal numbers. The details are in the documentation. You also need to take into account that numeric constants are in decimal format, rather than numeric.
Also, in the end, you need to convert back to a decimal format with the precision that you want. In that case, you might discover that float and decimal are equivalent.
I'm trying to determine the best way to truncate or drop extra decimal places in SQL without rounding. For example:
declare #value decimal(18,2)
set #value = 123.456
This will automatically round #value to be 123.46, which is good in most cases. However, for this project, I don't need that. Is there a simple way to truncate the decimals I don't need? I know I can use the left() function and convert back to a decimal. Are there any other ways?
ROUND ( 123.456 , 2 , 1 )
When the third parameter != 0 it truncates rather than rounds.
Syntax
ROUND ( numeric_expression , length [ ,function ] )
Arguments
numeric_expression
Is an expression of the exact numeric or approximate numeric data
type category, except for the bit data type.
length
Is the precision to which numeric_expression is to be rounded. length must be an expression of type tinyint, smallint, or int. When length is a positive number, numeric_expression is rounded to the number of decimal positions specified by length. When length is a negative number, numeric_expression is rounded on the left side of the decimal point, as specified by length.
function
Is the type of operation to perform. function must be tinyint, smallint, or int. When function is omitted or has a value of 0 (default), numeric_expression is rounded. When a value other than 0 is specified, numeric_expression is truncated.
select round(123.456, 2, 1)
SELECT Cast(Round(123.456,2,1) as decimal(18,2))
Here's the way I was able to truncate and not round:
select 100.0019-(100.0019%.001)
returns 100.0010
And your example:
select 123.456-(123.456%.001)
returns 123.450
Now if you want to get rid of the ending zero, simply cast it:
select cast((123.456-(123.456%.001)) as decimal (18,2))
returns 123.45
Actually whatever the third parameter is, 0 or 1 or 2, it will not round your value.
CAST(ROUND(10.0055,2,0) AS NUMERIC(10,2))
Do you want the decimal or not?
If not, use
select ceiling(#value),floor(#value)
If you do it with 0 then do a round:
select round(#value,2)
Another truncate with no rounding solution and example.
Convert 71.950005666 to a single decimal place number (71.9)
1) 71.950005666 * 10.0 = 719.50005666
2) Floor(719.50005666) = 719.0
3) 719.0 / 10.0 = 71.9
select Floor(71.950005666 * 10.0) / 10.0
Round has an optional parameter
Select round(123.456, 2, 1) will = 123.45
Select round(123.456, 2, 0) will = 123.46
ROUND(number, decimals, operation)
number => Required. The number to be rounded
decimals => Required. The number of decimal places to round number to
operation => Optional. If 0, it rounds the result to the number of decimal. If another value than 0, it truncates the result to the number of decimals. Default value is 0
SELECT ROUND(235.415, 2, 1)
will give you 235.410
SELECT ROUND(235.415, 0, 1)
will give you 235.000
But now trimming0 you can use cast
SELECT CAST(ROUND(235.415, 0, 1) AS INT)
will give you 235
This will remove the decimal part of any number
SELECT ROUND(#val,0,1)
SELECT CAST(Value as Decimal(10,2)) FROM TABLE_NAME;
Would give you 2 values after the decimal point. (MS SQL SERVER)
Another way is ODBC TRUNCATE function:
DECLARE #value DECIMAL(18,3) =123.456;
SELECT #value AS val, {fn TRUNCATE(#value, 2)} AS result
LiveDemo
Output:
╔═════════╦═════════╗
║ val ║ result ║
╠═════════╬═════════╣
║ 123,456 ║ 123,450 ║
╚═════════╩═════════╝
Remark:
I recommend using built-in ROUND function with 3rd parameter set to 1.
I know this is pretty late but I don't see it as an answer and have been using this trick for years.
Simply subtract .005 from your value and use Round(#num,2).
Your example:
declare #num decimal(9,5) = 123.456
select round(#num-.005,2)
returns 123.45
It will automatically adjust the rounding to the correct value you are looking for.
By the way, are you recreating the program from the movie Office Space?
Try like this:
SELECT cast(round(123.456,2,1) as decimal(18,2))
If you desire to take some number like 89.0904987 and turn it into 89.09 by simply omitting the undesired decimal places, simply use the following:
select cast(yourColumnName as decimal(18,2))
The following screenshot is from W3Schools SQL Data Types section, which describes what decimal(18,2) is doing:
Therefore,
select cast(89.0904987 as decimal(18,2))
gives you: 89.09
Please try to use this code for converting 3 decimal values after a point into 2 decimal places:
declare #val decimal (8, 2)
select #val = 123.456
select #val = #val
select #val
The output is 123.46
I think you want only the decimal value,
in this case you can use the following:
declare #val decimal (8, 3)
SET #val = 123.456
SELECT #val - ROUND(#val,0,1)
I know this question is really old but nobody used sub-strings to round. This as advantage the ability to round really long numbers (limit of your string in SQL server which is usually 8000 characters):
SUBSTRING('123.456', 1, CHARINDEX('.', '123.456') + 2)
I think we can go much easier with simpler example solution found in Hackerrank:
Problem statement: Query the greatest value of the Northern Latitudes
(LAT_N) from STATION that is less than 137.2345. Truncate your answer
to 4 decimal places.
SELECT TRUNCATE(MAX(LAT_N),4)
FROM STATION
WHERE LAT_N < 137.23453;
Solution Above gives you idea how to simply make value limited to 4 decimal points. If you want to lower or upper the numbers after decimal, just change 4 to whatever you want.
Mod(x,1) is the easiest way I think.
select convert(int,#value)