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Best way to check for “empty or null value”
What is best way to check if value is null or empty string in Postgres sql statements?
10 Answers
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How to get the CPU Usage in C#?
...up with this. I needed it for an 8 core machine where I wanted to monitor SQL server. For the code below then I passed in "sqlservr" as appName.
private static void RunTest(string appName)
{
bool done = false;
PerformanceCounter total_cpu = new PerformanceCounter("Process", "% Processor T...
Using group by on multiple columns
... values in a given column
COUNT(*) returns the number of rows in a table
SQL script examples about using aggregate functions:
Let's say we need to find the sale orders whose total sale is greater than $950. We combine the HAVING clause and the GROUP BY clause to accomplish this:
SELECT
orderI...
Specifying column name in a “references” migration
...ore info on migrations in general, and you may even end up putting calling SQL code directly in your migration. I would say ignore it, as it isn't a normal part of rails, you will get 0 performance out of it, as rails' default generated SQL queries take no advantage of it. link
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What are best practices that you use when writing Objective-C and Cocoa? [closed]
... is much less bloated and more memory-efficient when set to nonatomic.
6) SQLite can be a very, very fast way to cache large data sets. A map application for instance can cache its tiles into SQLite files. The most expensive part is disk I/O. Avoid many small writes by sending BEGIN; and COMMIT; b...
Difference between CTE and SubQuery?
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In MSSQL, you need to add a semicolon (;) before WITH, order wise you will get an error. it should be ;WITH blabla AS ...)
– Obinna Nnenanya
Dec 6 '18 at 18:01
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How to get parameters from the URL with JSP
...ed for input on your query
public int delete(int subjectid) {
String sql = "update tbl_subject set isdeleted= '1' where id = "+subjectid+"";
return template.update(sql);
}
share
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PostgreSQL database default location on Linux
What is the default directory where PostgreSQL will keep all databases on Linux?
8 Answers
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`find -name` pattern that matches multiple patterns
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My default has been:
find -type f | egrep -i "*.java|*.css|*.cs|*.sql"
Like the less process intencive find execution by Brendan Long and Stephan202 et al.:
find Documents \( -name "*.py" -or -name "*.html" \)
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Possible to perform cross-database queries with PostgreSQL?
...sult ), but is there anyway to perform a cross-database query using PostgreSQL?
8 Answers
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