Tutorial by Examples: table

TRUNCATE TABLE Helloworlds This code will delete all the data from the table Helloworlds. Truncate table is almost similar to Delete from Table code. The difference is that you can not use where clauses with Truncate. Truncate table is considered better than delete because it uses less transacti...

How to create User Model Class namespace App\Model\Table; use Cake\ORM\Table; class UsersTable extends Table { public function initialize(array $config) { $this->table('users'); //define table name $this->displayField('username'); // unique or other special field of...

CREATE TABLE new_table_name LIKE existing_table_name;

EditableAttribute sets whether users should be able to change the value of the class property. public class Employee { [Editable(false)] public string FirstName { get; set; } } Simple usage example in XAML application <Window x:Class="WpfApplication.MainWindow" ...

The TIMESTAMP column will show when the row was last updated. CREATE TABLE `TestLastUpdate` ( `ID` INT NULL, `Name` VARCHAR(50) NULL, `Address` VARCHAR(50) NULL, `LastUpdate` TIMESTAMP NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP ) COMMENT='Last Update' ;

If you have a "child table" formatted as JSON collection and stored in-row as JSON column, you can unpack this collection, transform it to table and join it with parent row. Instead of the standard JOIN operator, you should use CROSS APPLY. In this example, product parts are formatted as ...

If you can use memory-optimized tables, you can store JSON as text: CREATE TABLE ProductCollection ( Id int identity primary key nonclustered, Data nvarchar(max) ) WITH (MEMORY_OPTIMIZED=ON) Advantages of JSON in in-memory: JSON data is always in memory so there is no disk access Ther...

sqoop import \ --connect <rdbms-jdbc-url> \ --username <username> \ --password <password> \ --table <table-name> Example with Mysql: sqoop import \ --connect jdbc:mysql://mysql.example.com/testdb \ --username root \ --password root \ --table employees CSV file ...

Using --where tag sqoop import \ --connect <rdbms-jdbc-url> \ --username <username> \ --password <password> \ --table <table-name> \ --where "<condition>" Example with Mysql: sqoop import \ --connect jdbc:mysql://mysql.example.com/testdb \ --userna...

HTML: <div class="wrapper"> <div class="outer"> <div class="inner"> centered </div> </div> </div> CSS: .wrapper { height: 600px; text-align: center; } .outer { display: table; ...

The @switch annotation tells the compiler that the match statement can be replaced with a single tableswitch instruction at the bytecode level. This is a minor optimization that can remove unnecessary comparisons and variable loads during runtime. The @switch annotation works only for matches again...

Rebuilding indexes is done using the following statement ALTER INDEX All ON tableName REBUILD; This drops the index and recreates it, removing fragementation, reclaims disk space and reorders index pages. One can also reorganize an index using ALTER INDEX All ON tableName REORGANIZE; which ...

SELECT * INTO NewTable FROM OldTable Creates a new table with structure of old table and inserts all rows into the new table. Some Restrictions You cannot specify a table variable or table-valued parameter as the new table. You cannot use SELECT…INTO to create a partitioned table, even whe...

The following example can be used to find the total row count for a specific table in a database if table_name is replaced by the the table you wish to query: SELECT COUNT(*) AS [TotalRowCount] FROM table_name; It is also possible to get the row count for all tables by joining back to the table'...

MySQL allows to specify from which table the matching rows must be deleted -- remove only the employees DELETE e FROM Employees e JOIN Department d ON e.department_id = d.department_id WHERE d.name = 'Sales' -- remove employees and department DELETE e, d FROM Emp...

If your package isn't only a library, but has a piece of code that can be used either as a showcase or a standalone application when your package is installed, put that piece of code into __main__.py file. Put the __main__.py in the package_name folder. This way you will be able to run it directly ...

To make a jar, you need one or more class files. This should have a main method if it is to be run by a double click. For this example, we will use: import javax.swing.*; import java.awt.Container; public class HelloWorld { public static void main(String[] args) { JFrame f = ne...

A specifier that can be applied to the declaration of a non-static, non-reference data member of a class. A mutable member of a class is not const even when the object is const. class C { int x; mutable int times_accessed; public: C(): x(0), times_accessed(0) { } int get...

First, define a used defined table type to use: CREATE TYPE names as TABLE ( FirstName varchar(10), LastName varchar(10) ) GO Create the stored procedure: CREATE PROCEDURE prInsertNames ( @Names dbo.Names READONLY -- Note: You must specify the READONLY ) AS INSERT INTO d...

-- Create demo database CREATE DATABASE SQL2016_Demo ON PRIMARY ( NAME = N'SQL2016_Demo', FILENAME = N'C:\Dump\SQL2016_Demo.mdf', SIZE = 5120KB, FILEGROWTH = 1024KB ) LOG ON ( NAME = N'SQL2016_Demo_log', FILENAME = N'C:\Dump\SQL2016_Demo_log.ldf', ...