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Are nested transactions allowed in MySQL?
...Y) ENGINE=InnoDB;
START TRANSACTION;
INSERT
INTO t_test
VALUES (1);
SELECT *
FROM t_test;
id
---
1
SAVEPOINT tran2;
INSERT
INTO t_test
VALUES (2);
SELECT *
FROM t_test;
id
---
1
2
ROLLBACK TO tran2;
SELECT *
FROM t_test;
id
---
1
ROLLBACK;
SELECT *
FROM ...
What does collation mean?
... is a correctly ordered list:
Namibia
número
ñandú
ñú
obra
ojo
By selecting the correct collation, you get all this done for you, automatically :-)
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Two single-column indexes vs one two-column index in MySQL?
... the statement I provided.
Additionally, MySQL can only use one index per SELECT so a covering index would be the best means of optimizing your queries.
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How do I record audio on iPhone with AVAudioRecorder?
... code]);
NSLog(@"Error: %@ [%4.4s])" , [error localizedDescription], (char*)&errorCode);
}
NSLog(@"recording");
}
-(IBAction) stopRecording
{
NSLog(@"stopRecording");
[audioRecorder stop];
NSLog(@"stopped");
}
-(IBAction) playRecording
{
NSLog(@"playRecording");
// Init audio with playb...
How to auto-remove trailing whitespace in Eclipse?
...rences -> Java -> Editors -> Save Actions -> check Perform the selected actions on save -> check Additional actions -> click Configure.. -> go to Code organizing tab -> check Remove trailing whitespace -> select All lines.
Removing whitespace only from the lines I change...
Apply style to only first level of td tags
...>tr>td { border: solid 1px red; }
But! The ‘>’ direct-child selector does not work in IE6. If you need to support that browser (which you probably do, alas), all you can do is select the inner element separately and un-set the style:
.MyClass td { border: solid 1px red; }
.MyClass td...
Filter data.frame rows by a logical condition
...
To select rows according to one 'cell_type' (e.g. 'hesc'), use ==:
expr[expr$cell_type == "hesc", ]
To select rows according to two or more different 'cell_type', (e.g. either 'hesc' or 'bj fibroblast'), use %in%:
expr[expr$...
AngularJs: How to check for changes in file input fields?
...er="form-cntlr">
<form>
<button ng-click="selectFile()">Upload Your File</button>
<input type="file" style="display:none"
id="file" name='file' onchange="angular.element(this).scope().fileNameChanged(this)" />
<...
sqlite database default time value 'now'
...ime('%s','now'))
);
insert into example(data) values
('foo')
,('bar')
;
select
id
,data
,created_at as epoch
,datetime(created_at, 'unixepoch') as utc
,datetime(created_at, 'unixepoch', 'localtime') as localtime
from example
order by id
;
id|data|epoch |utc |localtime
1 |foo ...
Any difference between First Class Function and High Order Function
... supported because functions are inferior to other value types like int or char, in the sense that they cannot be explicitly defined (by a function body) wherever you want.
– wlnirvana
Apr 27 '17 at 23:58
...