Tutorial: SQL Server CE Query Tool

User friendly query designer and data manipulation tool for SQL Server CE

Introduction

CEQuery is written in C# with the help of VS2008 platform. Some of the features of this tool are described below

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SEQUENCE

A sequence is a database object used to generate sequence numbers for rows in the tables. It can be used for producing unique primary key values. A sequence is created using the CREATE SEQUENCE command.

A sequence is a user created database object that can be shared by multiple users to generate unique integers.

VIEWS

To reduce redundant data to the minimum possible, Oracles allows the creation of an object called a view. A view is mapped, to SELECT sentence. The table on which the view is based is described in the FORM clause of the SELECT statement.

Views are tables whose contents are taken or derived from other tables. Views themselves do not contain data. They just act as a window through which certain contents of a table can be viewed. Also, one can manipulate the contents of the original table these views.

SUBQUERIES

JOINS

Sometimes we require treating multiple tables as though they were a single entity. Then a single SQL sentence can manipulate data from all the tables. To achieve this, we have to join tables. Tables are joined on columns that have the same data type and data width in the tables. There are various types of joins. They are: -

(1) Self joins (joining a table to itself)
(2) Equi joins/ Inner joins
(3) Outer joins

CONSTRAINTS

The oracle server uses constraints to prevent invalid data entry into tables. Constraints prevent the deletion of a table if there are dependencies. The following constraints types are valid :
(1) NOT NULL
(2) UNIQUE
(3) PRIMARY KEY
(4) FOREIGN KEY
(5) CHECK

DATA CONSTRAINTS

DELETE OPERATIONS USED IN SQL
The verb DELETE in SQL is used to remove rows from table.

To remove
All the rows from a table. Or
A select set of rows from a table.

1) Delete all rows from the table
SYNTAX: -
DELETE FROM tablename;
EXAMPLE: -
SQL> delete from banking;


2) Removal of specified rows from the table.

SYNTAX: -

Tutorial : STRUCTURED QUERY LANGUAGE (SQL)

Introduction: