Beginning Microsoft SQL Server 2008 ... - S3 Tech Training

When you think about it, this seems like an easy thing to fix — just make use of the USE statement, but
before we test our new theory, we have to get rid of the old (OK, not that old) database:
USE MASTER;
DROP DATABASE Test;
We can then run our newly modified script:
CREATE DATABASE Test;
USE Test;
CREATE TABLE TestTable
(
col1 int,
col2 int
);
Unfortunately, this has its own problems:
Msg 911, Level 16, State 1, Line 3
Database ‘Test’ does not exist. Make sure that the name is entered correctly.
The parser tries to validate your code and finds that you are referencing a database with your USE command
that doesn’t exist. Ahh, now we see the need for our batches. We need the CREATE DATABASE
statement to be completed before we try to use the new database:
CREATE DATABASE Test;
GO
USE Test;
CREATE TABLE TestTable
(
col1 int,
col2 int
);
Now things work a lot better. Our immediate results look the same:
Command(s) completed successfully.
But when we run our INFORMATION_SCHEMA query, things are confirmed:
TABLE_CATALOG
--------------------
Test
(1 row(s) affected)
Chapter 11: Writing Scripts and Batches
Let’s move on to another example that shows an even more explicit need for precedence.
When you use an ALTER TABLE statement that significantly changes the type of a column or adds columns,
you cannot make use of those changes until the batch that makes the changes has completed.
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