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How to check if field is null or empty in MySQL?
...
Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
...
Eclipse does not highlight matching variables
...y:
window > preferences > java > editor > mark occurrences
Select all options available there.
Also go to:
Preferences > General > Editors > Text Editors > Annotations
Compare the settings for 'Occurrences' and 'Write Occurrences'
Make sure that you don't have the 'T...
Retrieve column names from java.sql.ResultSet
... metadata. See ResultSetMetaData
e.g.
ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM TABLE2");
ResultSetMetaData rsmd = rs.getMetaData();
String name = rsmd.getColumnName(1);
and you can get the column name from there. If you do
select x as y from table
then rsmd.getColumnLabel() wi...
Conversion failed when converting date and/or time from character string while inserting datetime
...s the recommend date/time data types for SQL Server 2008 or newer anyway.
SELECT
CAST('02-21-2012 6:10:00 PM' AS DATETIME2), -- works just fine
CAST('01-01-2012 12:00:00 AM' AS DATETIME2) -- works just fine
Don't ask me why this whole topic is so tricky and somewhat confusing - that...
Which version of PostgreSQL am I running?
...
Run this query from PostgreSQL:
SELECT version();
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How does Facebook Sharer select Images and other metadata when sharing my URL?
...s pulled from the source as a preview for their link. How are these images selected, and how can I ensure that any particular image on my page is always included in this list?
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How to delete the top 1000 rows from a table using Sql Server 2008?
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The code you tried is in fact two statements. A DELETE followed by a SELECT.
You don't define TOP as ordered by what.
For a specific ordering criteria deleting from a CTE or similar table expression is the most efficient way.
;WITH CTE AS
(
SELECT TOP 1000 *
FROM [mytab]
ORDER BY a1
)
DELET...
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...
Linq select objects in list where exists IN (A,B,C)
I have a list of orders .
I want to select orders based on a set of order statuses.
5 Answers
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Difference between SelectedItem, SelectedValue and SelectedValuePath
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Their names can be a bit confusing :). Here's a summary:
The SelectedItem property returns the entire object that your list is bound to. So say you've bound a list to a collection of Category objects (with each Category object having Name and ID properties). eg. ObservableCollection&l...