sql query for select first word of data from column

This will allow you to choose which part by simply filtering on RowNum. It will work no matter how many values you have...(assuming data is in a table called #temp)

SELECT 
FIELD1,Value,ROW_NUMBER() OVER(PARTITION BY FIELD1 ORDER BY FIELD1) RowNum
FROM 
#Temp T
CROSS APPLY STRING_SPLIT(FIELD1, ' ') T1

Specifically, this query will give you the first names. If you want last name, change it to RowNum=2 on last line.

SELECT Value FROM
(
SELECT 
        FIELD1,
        Value,
        ROW_NUMBER() OVER(PARTITION BY FIELD1 ORDER BY FIELD1) RowNum
    FROM 
        #Temp T
        CROSS APPLY STRING_SPLIT(FIELD1, ' ') T1
)
a 
WHERE RowNum=1

In Postgres you can use split_part()

split_part(the_column, ' ', 1);

Or, if you need to deal with multiple spaces, you can use regexp_split_to_array()

(regexp_split_to_array(the_column, 's+'))[1]

You can use "Substrig" and "charindex" functions to get what you want.

See this code as a demo on how to use it:

declare @name varchar(30)
set @name = 'shyam banarjee'
select SUBSTRING(@name,1,charindex(' ',@name)-1)

In your case, instead of being a variable in the select, it will be your column name.

You could also look at "computed column" if ever you want to have a new column that would only contains the firstname.