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Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
I've heard that SELECT * is generally bad practice to use when writing SQL commands because it is more efficient to SELECT columns you specifically need.
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Generating random strings with T-SQL
...st varchar(8000)
declare @step bigint = rand(@seed) * 2147483647;
select @alpha = 'qwertyuiopasdfghjklzxcvbnm'
, @digit = '1234567890'
, @specials = '_@# '
select @first = @alpha + '_@';
set @seed = (rand((@seed+@step)%2147483647)*2147483647);
select @length =...
When to use SELECT … FOR UPDATE?
Please help me understand the use-case behind SELECT ... FOR UPDATE .
2 Answers
2
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How to get a number of random elements from an array?
...- Math.random());
// Get sub-array of first n elements after shuffled
let selected = shuffled.slice(0, n);
DEMO:
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Get table names using SELECT statement in MySQL
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To get the name of all tables use:
SELECT table_name FROM information_schema.tables;
To get the name of the tables from a specific database use:
SELECT table_name FROM information_schema.tables
WHERE table_schema = 'your_database_name';
Now, to answer the...
Query to count the number of tables I have in MySQL
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SELECT COUNT(*) FROM information_schema.tables WHERE table_schema = 'dbName';
Source
This is mine:
USE databasename;
SHOW TABLES;
SELECT FOUND_ROWS();
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SQL Server - SELECT FROM stored procedure
...le result sets, each with its own schema. It's not suitable for using in a SELECT statement.
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How can I set the default value for an HTML element?
I thought that adding a "value" attribute set on the <select> element below would cause the <option> containing my provided "value" to be selected by default:
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How do I set the value property in AngularJS' ng-options?
...following forms:
For array data sources:
label for value in array
select as label for value in array
label group by group for value in array
select as label group by group for value in array track by trackexpr
For object data sources:
label for (key , value) in object
select as la...
How to create .ipa file using Xcode?
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In Xcode Version 10.0
Go to Window -> Organizer
Then select your app archive from archives
Then click the "Distribute App" button on right panel
Then follow the below steps
Step 1
Step 2
Step 3
Step 4
Step 5
Step 6 : Finally select the place you want to sa...