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Run PostgreSQL queries from the command line
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psql -U username -d mydatabase -c 'SELECT * FROM mytable'
If you're new to postgresql and unfamiliar with using the command line tool psql then there is some confusing behaviour you should be aware of when you've entered an interactive session.
For example, ...
Fastest way to count exact number of rows in a very large table?
I have come across articles that state that SELECT COUNT(*) FROM TABLE_NAME will be slow when the table has lots of rows and lots of columns.
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How do I find numeric columns in Pandas?
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You could use select_dtypes method of DataFrame. It includes two parameters include and exclude. So isNumeric would look like:
numerics = ['int16', 'int32', 'int64', 'float16', 'float32', 'float64']
newdf = df.select_dtypes(include=numer...
SQL Server query - Selecting COUNT(*) with DISTINCT
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Count all the DISTINCT program names by program type and push number
SELECT COUNT(DISTINCT program_name) AS Count,
program_type AS [Type]
FROM cm_production
WHERE push_number=@push_number
GROUP BY program_type
DISTINCT COUNT(*) will return a row for each unique count. What you want is C...
Install MySQL on Ubuntu without a password prompt
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sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password password your_password'
sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password_again password your_password'
sudo apt-get -y install ...
Insert all values of a table into another table in SQL
.... But the insert statement accepts values, but i would like it to accept a select * from the initial_Table. Is this possible?
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Access denied for user 'root'@'localhost' while attempting to grant privileges. How do I grant privi
...here ...
Now, what's missing then ?
On my system, I get this:
mysql> select version();
+------------+
| version() |
+------------+
| 5.5.21-log |
+------------+
1 row in set (0.00 sec)
mysql> SHOW GRANTS FOR 'root'@'localhost';
+------------------------------------------------------------...
How to build jars from IntelliJ properly?
...from IntelliJ:
Go to project structure:
Create a new artifact:
Select the main class, and be sure to change the manifest folder:
You have to change manifest directory:
<project folder>\src\main\java
replace "java" with "resources"
<project folder>\src\main\resources
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Correct way to remove plugin from Eclipse
...from Eclipse/STS :
Go to install folder of eclipse ----> plugin --> select required plugin and remove it.
Ex-
Step 1.
E:\springsource\sts-3.4.0.RELEASE\plugins
Step 2.
select and remove related plugins jars.
sh...
Disable Drag and Drop on HTML elements?
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This might work: You can disable selecting with css3 for text, image and basically everything.
.unselectable {
-moz-user-select: -moz-none;
-khtml-user-select: none;
-webkit-user-select: none;
/*
Introduced in IE 10.
See http://ie.mic...