Correct test answer?

Transact-SQL
#1

Choose the correct syntax to insert rows into dim_country table

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#2

Which ones are correct, i kept on trying but test always shows wrong. Any ideas?

#3

The 3rd one is correct. (I'm not sure about the 5th one, since that is not T-SQL (SQL Server) but some other rdbms.)

#4

Hi,

thanks for your answer but if I pick only third one and press submit it says incorrect.

#5

The first one already checked looked correct. Add the 3rd one to that. And likely the one after the last one selected.

So, overall: 3rd, 6th and 8th would be my best guess.

#6

nope, sadly

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#7

Assuming this is PostGreSQL, then 5 is also a valid option, in addition to 3,6 and 8.

1, 2 and 4 are syntactically incorrect.

#8

Hi again,

This is a PostGreSQL, yet the answer is still not valid.

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#9

I don't know what to tell you, except to install a PostGreSQL instance and try them out. Or simply try every answer combination until you get the "correct" answer. I'm not a PostGres expert, other than the ones I mentioned being invalid syntax.

#3 is valid syntax and should work for the example DDL posted, and #6 is also valid, unless there's a problem with the date formats in the VALUES clause.

2 Likes
#10

thanks for trying, I really appreciate it.

#11

Is a SERIAL column actually the same as people think of an IDENTITY column? In other words, while you can't insert into a classic IDENTITY column without jumping through a hoop or two, can you insert into a SERIAL column without jumping through such a hoop?

The example they give at the intersection pages 158/159 in the documentation looks like this and they explain it with the alternative.

CREATE TABLE tablename (
colname SERIAL
);
-- is equivalent to specifying:
CREATE SEQUENCE tablename_colname_seq AS integer;
CREATE TABLE tablename (
colname integer NOT NULL DEFAULT nextval('tablename_colname_seq')
);

The alternative is a sequence and there's absolutely NOTHING to prevent you from inserting into a column that has a default of "nextval" for a sequence. Of course, you could have a UNIQUE constraint on the column to prevent you from entering DUPLICATE values but there's nothing to prevent you from entering a value with a DEFAULT of a sequence "nextval".

Since they're saying the two are identical, I'm thinking you can enter values into a column designated as a SERIAL.

I don't have Postgres to try it with, either.

1 Like
#12

soo, which answers do you think should correct?

#13

I think we've given enough advice.

Have you tried any of these examples on a PostGreSQL instance? It's free to install and use. I've already made this suggestion.

We don't have the test in front of us, and I assume you're taking this test in order to get some certification. Actually using the product will teach you more about it that any test will.

1 Like
#14

Heh... you're the one that has to have Postgres loaded. And it looks like the "test" give you instant feedback. Spend a minute and try the bloody code! :wink:

1 Like
#15

I tried it and it seems indeed confusing as certain codes work but then i mark it test shows incorrect...