Oracle's 4th day advanced query

And the advantage of the essay is that you can force yourself to learn, what you did not want to learn today, or how much to learn

In the afternoon by a bug, just the two days of interns have been on leave, had to self (but today this matter interns estimated to be uncertain). Stored procedures in the judgment of equality, useless isnull, the result of the original value is null, resulting in the update into the insertion, the most painful is to deal with historical data, the other side has no Remote desktop, had to copy the database back to write scripts, but also to analyze the data, how many tables to deal with.

Overtime to nine, Flash is 10:30, see video Tutorial it:

1, Sort: MSSQL has top n,mysql has limit N, originally thought that Oracle does not have the corresponding will be very troublesome, did not think directly to a rownum keyword, directly can use ...

2, line number: Then look down, found that the line number can only be generated in the default order, and can only use < or <=, can not use > or >=, this is why ... There's no technical difficulty for Oracle, so why is this impacting the experience?

To use a different sort of line number, use the child table, but Oracle's child table actually does not have to alias, directly parentheses can

Look at a bit is also see, night overtime is already tired, don't want to see. Watch a movie, sleep.

Oracle's 4th day advanced query