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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 ...
How to get the connection String from a database
... Visual Studio go to Tools -> Connect to Database.
2] Under Server Name Select your Database Server Name (Let the list Populate if its taking time).
3] Under Connect to a Database, Select Select or enter a database name.
4] Select your Database from Dropdown.
5] After selecting Database try Test ...
Count(*) vs Count(1) - SQL Server
...
The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
SELECT COUNT(1) FROM dbo.tab800krows
SELECT COUNT(1),FKID FROM dbo.tab800krows GROUP BY FKID
SELECT COUNT(*) FROM dbo.tab800krows
SELECT COUNT(*),FKID FROM dbo.tab800krows GROU...
How to report an error from a SQL Server user-defined function
... For an inline-table-valued-function where the RETURN is a simple select, this alone doesn't work because nothing is returned - not even null, and in my case I wanted to throw an error when nothing was found. I didn't want to break down the inline function into a multi-statment one for obv...
How to return result of a SELECT inside a function in PostgreSQL?
... bigint
, ratio bigint) AS
$func$
BEGIN
RETURN QUERY
SELECT t.txt
, count(*) AS cnt -- column alias only visible inside
, (count(*) * 100) / _max_tokens -- I added brackets
FROM (
SELECT t.txt
FROM token t
WHERE t.charty...
How do I set up IntelliJ IDEA for Android applications?
...Program Files\Java\jdk{version}
Choose a New platform ( if there's not one selected ) , the SDK platform is the android platform at C:\Program Files\Android\android-sdk-windows.
Choose the android version.
Now you can write your program.
Compiling:
Near the Run button you need to select the drop...
get list of pandas dataframe columns based on data type
...
If you are just selecting columns by data type, then this answer is obsolete. Use select_dtypes instead
– Ted Petrou
Nov 3 '17 at 16:58
...
The current branch is not configured for pull No value for key branch.master.merge found in configur
...
To fix this problem in Eclipse, open the Windows menu and select Show View / Other / Git Repositories.
From the Git Repositories tab:
expand your local repository
right click on Remote
click on Create Remote...
Remote name = origin
next to IRI press the Change button
CTRL+SPACE o...
Rank function in MySQL
...
One option is to use a ranking variable, such as the following:
SELECT first_name,
age,
gender,
@curRank := @curRank + 1 AS rank
FROM person p, (SELECT @curRank := 0) r
ORDER BY age;
The (SELECT @curRank := 0) part allows the variable initializatio...
App Inventor 2 项目合并工具 AIMerge · App Inventor 2 中文网
... CountDownScreen1 project, then clicking on the “Project” dropdown and selecting “Export selected project (.aia) to my computer”. Figure 4 shows how to select a project and where to click to download the project.
Figure 4: Steps to download the CountDownScreen1 project
Developer 2 Work I...