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How do I check if a column is empty or null in MySQL?
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This will select all rows where some_col is NULL or '' (empty string)
SELECT * FROM table WHERE some_col IS NULL OR some_col = '';
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Convert Linq Query Result to Dictionary
... @pawan - that doesn't look right. I'd expect var servers = list.Select( s => new { s.ProjectName, Url = "tcp://" + s.BuildMachineName + ":" + s.PortNumber + "/CruiseManager.rem" } ).ToDictionary( s => s.ProjectName, s.Url ); This creates a dictionary keyed by project name of projec...
Select every Nth element in CSS
Is it possible to select, say, every fourth element in a set of elements?
4 Answers
4
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Converting a generic list to a CSV string
...s for us.
List<int> myValues;
string csv = String.Join(",", myValues.Select(x => x.ToString()).ToArray());
For the general case:
IEnumerable<T> myList;
string csv = String.Join(",", myList.Select(x => x.ToString()).ToArray());
As you can see, it's effectively no different. Beware...
XML Schema minOccurs / maxOccurs default values
...ml>
<body>
<xsl:for-each select="country">
<xsl:value-of select="countryName"/><br/>
<xsl:value-of select="capital"/><br/>
<xsl:value-of select="nation...
Get list of all tables in Oracle?
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SELECT owner, table_name
FROM dba_tables
This is assuming that you have access to the DBA_TABLES data dictionary view. If you do not have those privileges but need them, you can request that the DBA explicitly grants you...
Get type of all variables
...orage.mode unless you are trying to understand delays caused by round trip casts/coercions that occur when assigning and reading data to and from disk.
Ideology around R's triad typing system:
R's duck typing system has uncertainty in it. As an analogy, consider a ceramic cup, it can be used to h...
Search of table names
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I'm using this and works fine
SELECT * FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME LIKE '%%'
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HTML input file selection event not firing upon selecting the same file
Is there any chance to detect every file selection the user made for an HTML input of type file element?
7 Answers
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Remove Trailing Spaces and Update in Columns in SQL Server
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Try
SELECT LTRIM(RTRIM('Amit Tech Corp '))
LTRIM - removes any leading spaces from left side of string
RTRIM - removes any spaces from right
Ex:
update table set CompanyName = LTRIM(RTRIM(CompanyName))
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