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How to make a query with group_concat in sql server [duplicate]
...
Query:
SELECT
m.maskid
, m.maskname
, m.schoolid
, s.schoolname
, maskdetail = STUFF((
SELECT ',' + md.maskdetail
FROM dbo.maskdetails md
WHERE m.maskid = md.maskid
FOR X...
Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...k around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's outpu...
Retrieve the maximum length of a VARCHAR column in SQL Server
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Use the built-in functions for length and max on the description column:
SELECT MAX(LEN(DESC)) FROM table_name;
Note that if your table is very large, there can be performance issues.
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im...
Qt 5.1.1: Application failed to start because platform plugin “windows” is missing
...e main method before the QApplication call like this:
int main( int argc, char *argv[] )
{
QCoreApplication::addLibraryPath(".");
QApplication app( argc, argv );
...
return app.exec();
}
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Android getting value from selected radiobutton
... @Override
public void onClick(View v) {
// get selected radio button from radioGroup
int selectedId = radioGroup.getCheckedRadioButtonId();
// find the radiobutton by returned id
radioButton = (RadioButton) findViewById(selectedId);
...
Why is 128==128 false but 127==127 is true when comparing Integer wrappers in Java?
...the JLS (5.1.7).
If the value p being boxed is true, false, a byte, a char in the range \u0000 to \u007f, or an int or short number between -128 and
127, then let r1 and r2 be the results of any two boxing conversions
of p. It is always the case that r1 == r2.
A simple rule to remember wh...
How to get the sizes of the tables of a MySQL database?
...he size of a table (although you need to substitute the variables first):
SELECT
table_name AS `Table`,
round(((data_length + index_length) / 1024 / 1024), 2) `Size in MB`
FROM information_schema.TABLES
WHERE table_schema = "$DB_NAME"
AND table_name = "$TABLE_NAME";
or this query ...
Spring Boot JPA - configuring auto reconnect
...1.3
spring.datasource.testOnBorrow=true
spring.datasource.validationQuery=SELECT 1
As djxak noted in the comment, 1.4+ defines specific namespaces for the four connections pools Spring Boot supports: tomcat, hikari, dbcp, dbcp2 (dbcp is deprecated as of 1.5). You need to check which connection po...
Select parent element of known element in Selenium
I have a certain element that I can select with Selenium 1.
7 Answers
7
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Rails raw SQL example
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You can do this:
sql = "Select * from ... your sql query here"
records_array = ActiveRecord::Base.connection.execute(sql)
records_array would then be the result of your sql query in an array which you can iterate through.
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