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How many bits or bytes are there in a character? [closed]
How many bits or bytes are there per "character"?
2 Answers
2
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CHECK constraint in MySQL is not working
...GER `test_before_insert` BEFORE INSERT ON `Test`
FOR EACH ROW
BEGIN
IF CHAR_LENGTH( NEW.ID ) < 4 THEN
SIGNAL SQLSTATE '12345'
SET MESSAGE_TEXT := 'check constraint on Test.ID failed';
END IF;
END$$
DELIMITER ;
Prior to MySQL 5.5 you had to cause an error, e.g. ca...
How do you copy a record in a SQL table but swap out the unique id of the new row?
...
Try this:
insert into MyTable(field1, field2, id_backup)
select field1, field2, uniqueId from MyTable where uniqueId = @Id;
Any fields not specified should receive their default value (which is usually NULL when not defined).
...
How to copy a row and insert in same table with a autoincrement field in MySQL?
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Use INSERT ... SELECT:
insert into your_table (c1, c2, ...)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSER...
How to prevent SIGPIPEs (or handle them properly)
...? Is there a way to check if the other side of the line is still reading? (select() doesn't seem to work here as it always says the socket is writable). Or should I just catch the SIGPIPE with a handler and ignore it?
...
Rails 3: Get Random Record
...You can use the following trick on an indexed column (PostgreSQL syntax):
select *
from my_table
where id >= trunc(
random() * (select max(id) from my_table) + 1
)
order by id
limit 1;
share
|
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Removing first x characters from string?
How might one remove the first x characters from a string? For example, if one had a string lipsum , how would they remove the first 3 characters and get a result of sum ?
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how to exclude null values in array_agg like in string_agg using postgres?
...
SQL Fiddle
select
id,
(select array_agg(a) from unnest(canonical_users) a where a is not null) canonical_users,
(select array_agg(a) from unnest(non_canonical_users) a where a is not null) non_canonical_users
from (
SELE...
Parse (split) a string in C++ using string delimiter (standard C++)
...ollowing, you need add 2 not 1 due to the size of the delimiter which is 2 characters :) : std::string s = "scott>=tiger>=mushroom"; std::string delimiter = ">="; size_t last = 0; size_t next = 0; while ((next = s.find(delimiter, last)) != std::string::npos) { st...
What is the error “Every derived table must have its own alias” in MySQL?
...er), which can the be used to refer to it in the rest of the outer query.
SELECT ID FROM (
SELECT ID, msisdn FROM (
SELECT * FROM TT2
) AS T
) AS T
In your case, of course, the entire query could be replaced with:
SELECT ID FROM TT2
...