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C++ catching all exceptions
... { ... }
Which will allow you do use e.what(), which will return a const char*, which can tell you more about the exception itself. This is the construct that resembles the Java construct, you asked about, the most.
This will not help you if someone is stupid enough to throw an exception that doe...
Generate a random number in the range 1 - 10
... 1 and 10 you mean any float that is >= 1 and < 10, then it's easy:
select random() * 9 + 1
This can be easily tested with:
# select min(i), max(i) from (
select random() * 9 + 1 as i from generate_series(1,1000000)
) q;
min | max
-----------------+------------------...
How to find gaps in sequential numbering in mysql?
...r
Here's version that works on table of any size (not just on 100 rows):
SELECT (t1.id + 1) as gap_starts_at,
(SELECT MIN(t3.id) -1 FROM arrc_vouchers t3 WHERE t3.id > t1.id) as gap_ends_at
FROM arrc_vouchers t1
WHERE NOT EXISTS (SELECT t2.id FROM arrc_vouchers t2 WHERE t2.id = t1.id + ...
What does it mean by select 1 from table?
...
SELECT 1 FROM TABLE_NAME means, "Return 1 from the table". It is pretty unremarkable on its own, so normally it will be used with WHERE and often EXISTS (as @gbn notes, this is not necessarily best practice, it is, however, c...
How do I set the proxy to be used by the JVM
...
Awesome setting jvm arguement works for me like charm.. Thanks
– nanosoft
Dec 9 '14 at 4:51
...
How to select only date from a DATETIME field in MySQL?
...e a table in the MySQL database that is set up with DATETIME . I need to SELECT in this table only by DATE and excluding the time.
...
Newline in string attribute
... encoded value to represent a literal. In this case, I used the line feed (char 10). If you want to do "classic" vbCrLf, then you can use &#x0d;&#x0a;
By the way, note the syntax: It's the ampersand, a pound, the letter x, then the hex value of the character you want, and then finally a sem...
MySQL INNER JOIN select only one row from second table
...have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL statements before so I want to know what i'm doing wrong. Appreciate the help
...
What is the reason not to use select *?
...eople claim that you should specifically name each column you want in your select query.
20 Answers
...
MySQL: Insert record if not exists in table
...oDB;
Insert a record:
INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;
Query OK, 1 row affected (0.00 sec)
Records: 1 Duplicates: 0 Warnings: 0
...