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Using current time in UTC as default value in PostgreSQL
...rap it in a function:
create function now_utc() returns timestamp as $$
select now() at time zone 'utc';
$$ language sql;
create temporary table test(
id int,
ts timestamp without time zone default now_utc()
);
shar...
Why I cannot cout a string?
...
Use c_str() to convert the std::string to const char *.
cout << "String is : " << text.c_str() << endl ;
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Why does PostgreSQL perform sequential scan on indexed column?
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If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the ...
JPA EntityManager: Why use persist() over merge()?
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I noticed that when I used em.merge, I got a SELECT statement for every INSERT, even when there was no field that JPA was generating for me--the primary key field was a UUID that I set myself. I switched to em.persist(myEntityObject) and got just INSERT statements then...
How to disable HTML button using JavaScript?
...erence to the element collected through whatever means you like (e.g. querySelector)
– Quentin
Jun 27 '16 at 21:04
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Can't launch my app in Instruments: At least one target failed to launch
...To change your code signing identity for Xcode 6:
Click on your Project, Select the Target you are Profiling.
Build Settings -> Code Signing -> Code Signing Identity -> Release
Select your iOS developer profile.
Provisioning Profile: Let Xcode pick the correct Provisioning Profile for yo...
PostgreSQL wildcard LIKE for any of a list of words
... can use Postgres' SIMILAR TO operator which supports alternations, i.e.
select * from table where lower(value) similar to '%(foo|bar|baz)%';
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How to perform Unwind segue programmatically?
...our method to connect your source controller to the unwind IBAction.
3) Select the segue in the source view controller's document outline of the storyboard (it will be listed near the bottom), and give it an identifier.
4) Call the unwind segue using this method from source view controller, s...
Alter MySQL table to add comments on columns
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Script for all fields on database:
SELECT
table_name,
column_name,
CONCAT('ALTER TABLE `',
TABLE_SCHEMA,
'`.`',
table_name,
'` CHANGE `',
column_name,
'` `',
column_name,
'` ',
column_typ...
The maximum recursion 100 has been exhausted before statement completion
...@EntDt = '12/31/2009';
declare @dcnt int;
;with DateList as
(
select @STARTDATE DateValue
union all
select DateValue + 1 from DateList
where DateValue + 1 < convert(VARCHAR(15),@EntDt,101)
)
select count(*) as DayCnt from (
select DateValue,...