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MySQL Select Query - Get only first 10 characters of a value
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Using the below line
SELECT LEFT(subject , 10) FROM tbl
MySQL Doc.
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UPDATE multiple tables in MySQL using LEFT JOIN
...= t1.id
SET t1.col1 = newvalue
WHERE t2.id IS NULL
Note that for a SELECT it would be more efficient to use NOT IN / NOT EXISTS syntax:
SELECT t1.*
FROM t1
WHERE t1.id NOT IN
(
SELECT id
FROM t2
)
See the article in my blog for performance details...
how can I Update top 100 records in sql server
...derived table to define the desired sort order as below.
;WITH CTE AS
(
SELECT TOP 100 *
FROM T1
ORDER BY F2
)
UPDATE CTE SET F1='foo'
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PostgreSQL: How to pass parameters from command line?
...3="'2010-11-12'"
and then refer to the variables in sql as :v1, :v2 etc
select * from table_1 where id = :v1;
Please pay attention on how we pass string/date value using two quotes " '...' "
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How to animate the change of image in an UIImageView?
...ill first cross dissolve a new image and then add a bouncy animation:
var selected: Bool {
willSet(selected) {
let expandTransform:CGAffineTransform = CGAffineTransformMakeScale(1.15, 1.15);
if (!self.selected && selected) {
UIView.transitionWithView(self.imageView,
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How enumerate all classes with custom class attribute?
... faster (especially without empirical proof); you've basically written the Select extension method, and the compiler will generate a state machine just as it would if you called Select because of your use of yield return. Finally, any performance gains that might be obtained in the majority of case...
How to drop column with constraint?
...ing of constraints script:
DECLARE @sql NVARCHAR(MAX)
WHILE 1=1
BEGIN
SELECT TOP 1 @sql = N'alter table tbloffers drop constraint ['+dc.NAME+N']'
from sys.default_constraints dc
JOIN sys.columns c
ON c.default_object_id = dc.object_id
WHERE
dc.parent_object_id = OBJ...
How can I select and upload multiple files with HTML and PHP, using HTTP POST?
... </body>
</html>
Here's what it looks like in Chrome after selecting 2 items in the file dialog:
And here's what it looks like after clicking the "Upload" button.
This is just a sketch of a fully working answer. See PHP Manual: Handling file uploads for more information on prop...
What is the PostgreSQL equivalent for ISNULL()
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SELECT CASE WHEN field IS NULL THEN 'Empty' ELSE field END AS field_alias
Or more idiomatic:
SELECT coalesce(field, 'Empty') AS field_alias
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MySQL - UPDATE query based on SELECT Query
...can go here
ANSI SQL syntax:
UPDATE tableA SET validation_check =
(SELECT if(start_DTS > end_DTS, 'VALID', '') AS validation_check
FROM tableA
INNER JOIN tableB ON name_A = name_B
WHERE id_A = tableA.id_A)
Pick whichever one seems most natural to you.
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