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Regular cast vs. static_cast vs. dynamic_cast [duplicate]
...For example, the C-style cast would allow an integer pointer to point to a char.
char c = 10; // 1 byte
int *p = (int*)&c; // 4 bytes
Since this results in a 4-byte pointer pointing to 1 byte of allocated memory, writing to this pointer will either cause a run-time error or will overwri...
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...
git ignore vim temporary files
...ension to find another file that can be used.
* First decrement the last char: ".swo", ".swn", etc.
* If that still isn't enough decrement the last but one char: ".svz"
* Can happen when editing many "No Name" buffers.
*/
if (fname[n - 1] == 'a') /* ".s?a" */
{
if (fname[n - 2]...
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...
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.
...
How can I convert String to Int?
... is successful. I.e. in this case, x = 0 if the string has any non-integer characters, or x = value of string-as-integer otherwise. So the neat thing is this is one short expression which tells you if casting is successful or not, AND stores the cast integer in a variable at same time. Obviously you...
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...
Inner join vs Where
... for the query using the inner join:
-- with inner join
EXPLAIN PLAN FOR
SELECT * FROM table1 t1
INNER JOIN table2 t2 ON t1.id = t2.id;
SELECT *
FROM TABLE (DBMS_XPLAN.DISPLAY);
-- 0 select statement
-- 1 hash join (access("T1"."ID"="T2"."ID"))
-- 2 table access full table1
-- 3 table access ful...
Ordering by specific field value first
...QL FIELD function.
If you want complete sorting for all possible values:
SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "core", "board", "other")
If you only care that "core" is first and the other values don't matter:
SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "co...
PHP method chaining?
...imed at creating a DSL. Ex: $foo->setBar(1)->setBaz(2) vs $table->select()->from('foo')->where('bar = 1')->order('ASC). The latter spans multiple objects.
– Gordon
Sep 16 '10 at 7:32
...