SQL question regarding the insertion of empty tuples to prepare for update statements

I am making a table th开发者_StackOverflow中文版at will be borrowing a couple of columns from another table, but not all of them. Right now my new table doesn't have anything in it. I want to add X number of empty tuples to my table so that I can then begin adding data from my old table to my new table via update statements.

Is that the best way to do it? What is the syntax for adding empty rows? Thanks

Instead of inserting nulls and then updating them, cant you just insert data from the other table directly. using something like this -

INSERT INTO Table1 (col1, col2, col3)
SELECT column1, column2, column3
FROM Table2
WHERE <some condition>

If you still want to insert empty records, then you will have to make sure that all your columns allow nulls. Then you can use something like this -

Table1

PrimaryKey_Col | col1 | col2 | col3

Insert INTO Table1 (PrimaryKey_col) values (<some value>)

This will make sure your a new row is inserted with a primary key and the rest of the columns are nulls. And these records can be updated later.

No, this is not even a good way, let alone the best way.

If you look at it conceptually adding empty rows serves no purpose. In databases each row of a table corresponds to a true statement (fact). Adding a row with all NULLs (even if possible) records nothing and represents inconsistent data on its own. Especially having multiple empty records.

Also, if you are even able to add a row with all NULLs to a table that's an indication that you have no data integrity rules for the row so and that's mostly what databases are about - integrity rules and quality of data. A well designed database should not accept contradictory or meaningless data (and empty row is meaningless)

As Pavanred answered inserting real data is a single command, so there is no benefit in making it two or more commands.