I am having to change one of the columns in table which currently is Float to Varchar, but when I use alter command, it stores some of the longer numbers in Scientific Notation.
Can I avoid this?
If not, is there a way to easily update the table later to store the scientific notation as normal integer?
Thanks
Please check the link
convert float into varchar in SQL server without scientific notation
You can cast the float to varchar(max)
How to convert float to varchar in SQL Server
I have a workaround for this I have used in the past. Dan isn't far off, but just casting it won't work. You can alter the table by adding a new varchar column then using str and ltrim to update the new column from the old float column. Say your varchar column was varchar(50), use something like:
update YourTable set NewColumn = ltrim(str(OldColumn, 50))
str() converts to character data, ltrim() gets rid of any extra blanks on the left. You can then always get rid of the old column. Feels janky but should work for you.
Related
I'm trying to convert a string to a decimal using this command:
SELECT cast(minimum_ticket_price AS DECIMAL(6,2)
FROM all_event_details
WHERE minimum_ticket_price ~ E'^\\d+$';
But this doesn't actually update anything in my database. It just displays the selected column in my terminal. Do I need to combine the select with an update? I've tried that but I must have the syntax wrong as I'm not able to get the conversion saved in the database.
Here's what I tried:
UPDATE all_event_details
SET minimum_ticket_price = cast(minimum_ticket_price AS DECIMAL(6,2))
WHERE ( minimum_ticket_price <> '') IS TRUE;;
Updating to a data type which minimum_ticket_price column's data can support is possible otherwise it will give an error.
for example if minimum_ticket_price column data type is varchar then your code must work.
What are you doing?
First add new column, decimal(but I'm goint to suggest to use the basics data type such real or double precision, are most efficient)
ALTER TABLE my_table ADD COLUMN minimum_ticket_priceR real ;
than
UPDATE all_event_details
SET minimum_ticket_priceR = to_number(coalesce(minimum_ticket_price,"0"),"999999D99") --for each row
than I'm going to suggest to drop the colum minimum_ticket_price and rename the other column (ever with ALTER TABLE):
What you did is not to understand, if minimum_ticket_price is string, you cannot set a number... and if is a number has no meaning to set it as string
I have a column in a table with a varchar datatype. It has 15 digits after the decimal point. Now I am having a hard time converting it to a numeric format.. float, double etc.
Does anyone have any suggestions?
Example :
Table1
Column1
-------------------
-28.851540616246499
-22.857142857142858
-26.923076923076923
76.19047619047619
I tried using the following statements and it doesn't seem to work :
update table1
set Column1 = Convert(float,column1)..
Any suggestions ?
You can use the decimal data type and specify the precision to state how many digits are after the decimal point. So you could use decimal(28,20) for example, which would hold 28 digits with 20 of them after the decimal point.
Here's a SQL Fiddle, showing your data in decimal format.
Fiddle sample:
create table Table1(MyValues varchar(100))
insert into Table1(MyValues)
values
('-28.851540616246499'),
('-22.857142857142858'),
('-26.923076923076923'),
('76.19047619047619')
So the values are held as varchar in this table, but you can cast it to decimal as long as they are all valid values, like so:
select cast(MyValues as decimal(28,20)) as DecimalValues
from table1
Your Sample
Looking at your sample update statement, you wouldn't be able to convert the values from varchar to a numeric type and insert them back in to the same column, as the column is of type varchar. You would be better off adding a new column with a numeric data type and updating that.
So if you had 2 columns:
create table Table1(MyValues varchar(100), DecimalValues decimal(28,20))
You could do the below to update the numeric column with the nvarchar values that have been cast to decimal:
update Table1
set DecimalValues = cast(MyValues as decimal(28,20))
I think you're trying to actually change the data type of that column?
If that is the case you want to ALTER the table and change the column type over to float, like so:
alter table table1
alter column column1 float
See fiddle: http://sqlfiddle.com/#!6/637e6/1/0
You would use CONVERT if you're changing the text values to numbers for temporary use within a query (not to actually permanently change the data).
I have an imported database which contain lots of float field.
When I imported it, all the float field converted to string and I need to convert it back.
I try alter table to change the data type but I keep getting error (even if the row is empty or null).
EDIT : The server is curently down so I can't get the error message at the moment. My DBMS is SQL Server.
you can do so if all data are really numeric type.
There may be some data which hv null --no problem here.
There may be some data which are blank(('') but not null--problem is because of this.
First you make a select query to retrieve all data which are blank
say,
Select * from table1 where col=''
now update these rows with null
update table1 set col=null where col=''
After this,I think you can easily convert it to float
References: error converting data type varchar column to float.
You can first add a new field in your table with datatype float and then update it using convert function:
UPDATE #tbl
SET
num = convert(FLOAT, text)
SELECT *
FROM
#tbl
I need help with a SQL convert statement. I have NetQuanity (masterTable) which is a varchar(15) and I have another table with Purchase price (PO TABLE) which is money. When I try to multiply them in a SQL view is gives me the error:
If your field is a VARCHAR, you'll need to CAST to the appropriate data type prior to your operation. e.g.
CAST(myVarCharField as INT) * myIntField
Be forewarned however, if you attempt to CAST this field to a numeric data type and it's not numeric, you'll be in the same boat.
I would recommend using CAST over CONVERT in your example, for the following reason defined in this SO post:
Related: T-SQL Cast versus Convert
Maybe try using the CONVERT function? CONVERT(money,NetQuantity).
First of all you have a data definition problem.
The first thing is to eliminate any non-numeric entries in the master table.
SELECT whatever FROM masterTable WHERE ISNUMERIC(NetQuanity)=1
The next step is to include this as a sub-query in the calculation.
In this query use CONVERT or CAST to convert the valid quanities to integer.
i.e.
CONVERT(INT, NetQuantity)
This is on SQL Server 2008.
I have several columns I want to convert from money and decimal to varchar, for example a column called item_amount.
How will these values be converted?
Will it be the same as convert(varchar, item_amount)? Running a query like select item_amount, convert(varchar, item_amount) from <table> renders the columns identically, which is what I would expect and want.
I should be safe from possible truncation, correct?
Assuming there are enough characters in the varchar column (which would be 39, since the max precision for a decimal column is 38 + 1 character for the decimal point). None of the numeric values are even close to 38 digits, most in the 3-5 range.
I've run this command successfully on a test table and want to make sure I'm not overlooking or forgetting something that's going to screw me: alter table <mytable> alter column item_amount varchar(39) default '0' (this is after droping the existing default ((0)) constraint).
With regard to the way conversion is done, yes you are correct as long as the VARCHAR column you are placing it in has the right number of characters available you will be set to go.
With regards to your change of amount to varchar, you should be fine here as it will do the conversion.
I just have to note that it doesn't sound like a good idea to do this as you are no longer interacting with numbers for sorting, filtering, etc....but just a note.