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Return Boolean Value on SQL Select Statement
How to return a boolean value on SQL Select Statement?
9 Answers
9
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Why does MYSQL higher LIMIT offset slow the query down?
...h more than 16 million records [2GB in size]. The higher LIMIT offset with SELECT, the slower the query becomes, when using ORDER BY *primary_key*
...
Multiple queries executed in java in single statement
...s wondering if it is possible to execute something like this using JDBC.
"SELECT FROM * TABLE;INSERT INTO TABLE;"
Yes it is possible. There are two ways, as far as I know. They are
By setting database connection property to allow multiple queries,
separated by a semi-colon by default.
By callin...
In what cases do I use malloc and/or new?
... Always use new.
If you need a big chunk of data just do something like:
char *pBuffer = new char[1024];
Be careful though this is not correct:
//This is incorrect - may delete only one element, may corrupt the heap, or worse...
delete pBuffer;
Instead you should do this when deleting an arra...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...and re-try where necessary.
Some attempted solutions also fail to consider SELECT races. If you try the obvious and simple:
-- THIS IS WRONG. DO NOT COPY IT. It's an EXAMPLE.
BEGIN;
UPDATE testtable
SET somedata = 'blah'
WHERE id = 2;
-- Remember, this is WRONG. Do NOT COPY IT.
INSERT INTO testt...
IOCTL Linux device driver [closed]
...vr_version_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%s\n", DRIVER_RELEASE);
}
static DEVICE_ATTR(version, S_IRUGO, mydrvr_version_show, NULL);
And during driver setup:
device_create_file(dev, &dev_attr_version);
You would then ha...
Email validation using jQuery
...l could be written in better way. None part of domain can start with other char than [a-z0-9] (case insensitive). Also, valid e-mail (and domain) has some len limit, which is also not tested.
– tomis
Jul 5 '13 at 8:42
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Select + copy text in a TextView?
Is there a way to allow the user to select / copy text in a TextView? I need the same functionality of EditText where you can long-press the control and get the popup options of select all / copy, but I need the control to look like a TextView.
...
Hibernate Criteria returns children multiple times with FetchType.EAGER
....class)
.list();
List result = session.createQuery("select o from Order o left join fetch o.lineItems").list();
All of these examples produce the same SQL statement:
SELECT o.*, l.* from ORDER o LEFT OUTER JOIN LINE_ITEMS l ON o.ID = l.ORDER_ID
Want to know why th...
Convert timestamp to date in MySQL query
...
SELECT * FROM users WHERE DATE_FORMAT(FROM_UNIXTIME(users.user_created_at),'%Y-%b-%e') = '2015-03-06' is this correct format or should i modify this?
– Dheeraj Thedijje
Mar 7 '18 at 11:4...