Add a column of zeros to table sql server

2018-06-08 03:16:47

Possible Duplicate:
Add column, with default value, to existing table in SQL Server

I have a table in sql server, but want to add a extra column full of zeros

What would be the best approach to do this

att1 att2
---------
1.0   5.8
2.7   3.8
5.1   6.8

becomes

att1 att2  extra
----------------
1.0   5.8   0.0
2.7   3.8   0.0
5.1   6.8   0.0

If I recall correctly, it should be something like:

ALTER TABLE table_name 
ADD extra REAL DEFAULT 0

See: http://msdn.microsoft.com/en-us/library/ms190273.aspx

See: Add a column with a default value to an existing table in SQL Server

I understand this column will always have value of 0.0. Then it does not have to be a real column

CREATE TABLE extraColumn (
     att1   float  NULL
    ,att2   float  NULL
    ,extra AS 0.0 
)

But if you need that, you can persist it

CREATE TABLE extraColumn (
     att1   float  NULL
    ,att2   float  NULL
    ,extra AS 0.0  PERSISTED 
)

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