I have a varchar column that has numbers with .0
This column has both numeric data and non-numeric data.
I first tried to convert data type to integer, but since there is non-numeric data type, it would not let me.
How do I remove .0 (from all numbers that has .0)?
So, for example, 100.0 should be 100
I am not trying to use select, cast or truncate as I need to actually modify the existing data.
Thanks.
Since the column has both numeric and non-numeric data it is not enough to just check if it ends with '.0'.
You should also check if it is a numeric value, which can be done with TRY_CAST():
UPDATE tablename
SET col = LEFT(col, LEN(col) - 2)
WHERE col LIKE '%.0' AND TRY_CAST(col AS FLOAT) IS NOT NULL
See the demo.
Assuming you want to update your table...
where x = your table name
yourfieldname = the field name you need to update.
.
UPDATE table X
SET yourfieldName = left(yourfieldname,len(yourieldName)-2)
WHERE right(yourfieldName,2)='.0')
-- or perhaps where yourfieldname like '%.0' would be faster...
Should: update all fields ending in .0 would need to test to see which where clause would be faster depending on indexes. if speed is a consideration. If not; and this is a 1 and done... does it matter?
Be sure to test on a subset/copy table!
Assumes you don't have a spaces after the .0... or any non-display characters.. If you do you'll need to trim off the spaces and replace the non-display characters with empty string ''
Just another option
Example
Declare #YourTable table (SomeCol varchar(50))
Insert Into #YourTable values
('100.0')
,('1001.0')
,('Not Numeric')
,('-200.05')
,('10,250.0')
Update #YourTable
set SomeCol = format(try_convert(money,SomeCol),'#.######')
From #YourTable
Where try_convert(money,SomeCol) is not null
The Updated Table
SomeCol
100
1001
Not Numeric
-200.05
10250
Related
I am inserting data from one table to another so when inserting I got above error mentioned in title
Insert into dbo.source(
title
)
Select
Title from dbi.destination
title in dbo.source table is of INT data type and title in dbo.destination table is of Varchar data type and I have data like abc, efg, etc. in the dbo.destination table.
So how to solve this now or is it possible to convert and insert values?
You can use SQL Server try_cast() function as shown below. Here is the official documentation of TRY_CAST (Transact-SQL).
It Returns a value cast to the specified data type if the cast succeeds; otherwise, returns null.
Syntax
TRY_CAST ( expression AS data_type [ ( length ) ] )
And the implementation in your query.
INSERT INTO dbo.source (title)
SELECT try_cast(Title AS INT)
FROM dbi.destination
Using this solution you need to be sure you have set the column allow null true otherwise it will give error.
If you do not want to set the allow null then you need minor changes in select query as shown below - passing the addition criteria to avoid null values.
Select ... from ... where try_cast(Title AS INT) is not null
You must use isnumeric method of SQL for checking is data numeric or not
CONVERT(INT,
CASE
WHEN IsNumeric(CONVERT(VARCHAR(12), a.value)) = 1 THEN CONVERT(VARCHAR(12),a.value)
ELSE 0 END)
Think about your data types - obviously you cannot have a text string like 'abc' in a column that is defined to hold integers.
It makes no sense to copy a string value into an integer column, so you have to confirm how you want to handle these - do you simply discard them (what is the impact of throwing data away?) or do you replace them with some other value?
If you want to ignore them and use NULL in place then use:
INSERT dbo.Source (Title)
SELECT CASE
WHEN ISNUMERIC(Title) = 1 THEN CAST(Title as INT)
ELSE NULL
END
FROM dbo.Destination
If you want to replace the value then simply change NULL above to the value you want e.g. 0
You can use regex to root out non numeric characters
Insert into dbo.source(
title
)
Select
case when Title not like '%[^0-9]%' then null else cast(Title as int) end as Title
from dbi.destination
Just filter only numeric field from destination table like as below:
Insert into dbo.source(
title
)
Select
Title from dbi.destination
where ISNUMERIC(Title) = 1
I have a Table with a computed column that uses a scalar function
CREATE FUNCTION [dbo].[ConvertToMillimetres]
(
#fromUnitOfMeasure int,
#value decimal(18,4)
)
RETURNS decimal(18,2)
WITH SCHEMABINDING
AS
BEGIN
RETURN
CASE
WHEN #fromUnitOfMeasure=1 THEN #value
WHEN #fromUnitOfMeasure=2 THEN #value * 100
WHEN #fromUnitOfMeasure=3 THEN #value * 1000
WHEN #fromUnitOfMeasure=4 THEN #value * 25.4
ELSE #value
END
END
GO
The table has this column
[LengthInMm] AS (CONVERT([decimal](18,2),[dbo].[ConvertToMillimetres]([LengthUnitOfMeasure],[Length]))) PERSISTED,
Assuming that the [Length] on the Table is 62.01249 and [LengthUnitOfMeasure] is 4 the LengthInMm computed value comes with 1575.11 but when i run the function directly like
SELECT [dbo].[ConvertToMillimetres] (4, 62.01249) GO
It comes with 1575.12
[Length] column is (decimal(18,4, null))
Can anyone tell why this happens?
I'm not sure this really counts as an answer, but you've perhaps got a problem with a specific version of SQL?
I just had a go at replicating it (on a local SQL 2014 install) and got the following:
create table dbo.Widgets (
Name varchar(20),
Length decimal(18,4),
LengthInMm AS [dbo].[ConvertToMillimetres] (4, Length) PERSISTED
)
insert into dbo.Widgets (Name, Length) values ('Thingy', 62.01249)
select * from dbo.Widgets
Which gives the result:
Name Length LengthInMm
-------------------- --------------------------------------- ---------------------------------------
Thingy 62.0125 1575.12
(1 row(s) affected)
Note that your definition uses [LengthInMm] AS (CONVERT([decimal](18,2),[dbo].[ConvertToMillimetres]([LengthUnitOfMeasure],[Length]))) PERSISTED, but that doesn't seem to make a difference to the result.
I also tried on my PC (Microsoft SQL Server 2012 - 11.0.2100.60 (X64)). Works fine:
CREATE TABLE dbo.data(
LengthUnitOfMeasure INT,
[Length] decimal(18,4),
[LengthInMm] AS (CONVERT([decimal](18,2),[dbo].[ConvertToMillimetres]([LengthUnitOfMeasure],[Length]))) PERSISTED
)
INSERT INTO dbo.data (LengthUnitOfMeasure, [Length])
SELECT 4, 62.01249
SELECT *
FROM dbo.data
/*
RESULT
LengthUnitOfMeasure Length LengthInMm
4 62.0125 1575.12
*/
I think, I found the answer:
Lets see what you are saying:
There is a column with decimal(18,4) data type.
There is a calculated column which depend on this column.
The result differs when you select the calculated field and when you provide the same result manually. (Right?)
Sorry, but the input parameters are not the same:
The column in the table is decimal(18,4). The value you are provided manually is decimal(7,5) (62.01249)
Since the column in the table can not store any values with scale of 5, the provided values will not be equal. (Furthermore there is no record in the table with the value of 62.01249 in the Length column)
What is the output when you query the [Length] column from the table? Is it 62.0124? If yes, then this is the answer. The results can not be equal since the input values are not equal.
To be a bit more specific: 62.01249 will be casted (implicit cast) to 62.0125.
ROUND(25.4 * 62.0124, 2) = 1575.11
ROUND(25.4 * 62.0125, 2) = 1575.12
EDIT Everybody who tried to rebuild the schema made the same mistake (Including me). When we (blindly) inserted the values from the original question into our instances, we inserted the 62.01249 into the Length column -> the same implicit cast occured, so we have the value 62.0125 in our tables.
Is there any way to deal with SQL casts if the input data is corrupt?
Let's say I have a column of datatype NVarchar(10) and want to cast this column to int.
Let's also say that some of the nvarchar values are corrupt, so they can't be converted to int.
Is there any way to silently ignore these, default them to 0 or some such?
DECLARE #t TABLE (Numbers VARCHAR(20))
INSERT INTO #t
VALUES
('30a'),('30'),('100'),
('100a'),('200'),('200a')
SELECT CASE
WHEN ISNUMERIC(Numbers) = 1
THEN CAST(Numbers AS INT) ELSE NULL END AS Number
FROM #t
ISNUMERIC Function returns 1 when it is an integer value you can use this function.
Result
Number
NULL
30
100
NULL
200
NULL
it will cast the integer values to INT and ignore the values that cannot be cast to Int
Try this with PatIndex() function:
select id, val
from t
where patindex('%[^0-9]%',val) = 0
Note: above query is filtering out corrupted values, if you need to bring them in with 0 values, please use a case expression as below.
select id, case when patindex('%[^0-9]%',val) = 0
then convert(int, val)
else 0 end val
from t
Fiddle demo for both queries
I'll be the unpopular one and advise REGEX because ISNUMERIC, while sometimes useful, doesn't catch everything. This answer on SO excellently covers some REGEX concepts, for instance:
One numeric digit
Probably the easiest one of the bunch:
WHERE Column LIKE '[0-9]'
For more details, here's a useful REGEX workbench by Phil Factor and Robyn Pae.
What is the right practice of checking NULLs in SQL Case ?
1) Using ISNULL()
WHEN (ISNULL(TABLE.COLUMN,0) > 0) THEN ....
2) Using IS NULL
WHEN TABLE.COLUMN IS NOT NULL THEN ....
If you are checking any condition then always use 'is null' and if replacing any value with a different one, then use isnull(a,b).
Check the following -
http://msdn.microsoft.com/en-us/library/ms184325.aspx
Read the last line specially!!!
Second one is right if you want to check for null value in SQL case..
Both are correct if the values in the column are either greater than 0 or null.
You can refer to this post if you want to know about the weird behavior of nulls in SQL Server.
This is also another approach to check for NON NULL values.
Checking for length of the column if it is greater than 1 or equal 1 then its a NON NULL
value.
declare #emp table
(
fname varchar(50)
);
INSERT into #emp VALUES('vishwanath');
INSERT into #emp VALUES('chetan');
INSERT into #emp VALUES(NULL);
INSERT into #emp VALUES(NULL);
SELECT * FROM #emp
where len(fname)>=1 and fname<>'';
Gives..
fname
--------------------------------------------------
vishwanath
chetan
when you are checking whether a column is null or not it is better to use
col IS NULL
when you use ISNULL(TABLE.COLUMN,0) > 0) function , null values have to be converted to zero fist then should take all values greater than zero
this function is useful in another occasion. lets say if I want to return all the null values as well as the negative values.
so the query would be
select * from table where col is null or col<0
this can be re-written as
select * from table isnull(col,-1)<0
Both are correct in there cause, however ISNULL can be helpfull when you want to use a constant value instead of NULL in that column while calculating SUM, average, etc.
For example you can check :http://www.w3schools.com/sql/sql_isnull.asp
Due to this feature I personally use ISNULL/COALESCE for calculation purposes.
I want to write a query to see if a category field is within a certain range. The problem is the field can contain null, text or numeric text prefixed by '#' character.
Does anybody know of SQL that will strip the non numerics and allow me to do the following check.
category > 1 and category < 100
Here is a sample of what the field category can contain:
#230.1
#200
Null
text
I am using SQL Server 2000
I appears astander's solution is functional. You should consider however a few points:
If the table holds more than a few thousand rows, and if this type of query is to be run frequently, it may be beneficial to introduce a new column to hold the numeric value of the category (if available, null otherwise). This will be more efficient for two reasons: as written, SQL needs to scan the table, completely, i.e.it needs to review every single row; also it needs to perform all these conversion which are a bit expensive, CPU-wise.
You may consider introducing some extra logic to normalize the category field. For example to get rid of common leading or trailing characters etc. This will "rescue" several category codes which would otherwise translate to null wouldn't be able to participate in these filters.
Try something like this
DECLARE #Table TABLE(
Val VARCHAR(200)
)
INSERT INTO #Table (Val) SELECT '#230.1'
INSERT INTO #Table (Val) SELECT '#200'
INSERT INTO #Table (Val) SELECT '210'
INSERT INTO #Table (Val) SELECT NULL
INSERT INTO #Table (Val) SELECT 'text'
SELECT *
FROM (
SELECT CASE
WHEN ISNUMERIC(Val) = 1
THEN CAST(Val AS FLOAT)
WHEN LEN(Val) > 1 AND ISNUMERIC(RIGHT(Val,LEN(Val)-1)) = 1
THEN CAST(RIGHT(Val,LEN(Val)-1) AS FLOAT)
END Num
FROM #Table
WHERE Val IS NOT NULL
AND (
ISNUMERIC(Val) = 1
OR (
LEN(Val) > 1
AND ISNUMERIC(RIGHT(Val,LEN(Val)-1)) = 1
)
)
) Numbers
WHERE Num BETWEEN 205 AND 230