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SQL IN Operator
SQL IN Operator The IN Operator The IN operator allows you to specify multiple values in a WHERE clause. SQL IN Syntax SELECT column_name(s)FROM table_nameWHERE column_name IN (value1,value2,...) IN Operator Example The "Persons" table: P_Id LastName FirstName Addre…[ More ]
SQL Wildcards
SQL Wildcards SQL wildcards can be used when searching for data in a database. SQL Wildcards  SQL wildcards can substitute for one or more characters when searching for data in a database. SQL wildcards must be used with the SQL LIKE operator. With SQL, the following wildcards can…[ More ]
SQL LIKE Operator
SQL LIKE Operator The LIKE operator is used in a WHERE clause to search for a specified pattern in a column. The LIKE Operator The LIKE operator is used to search for a specified pattern in a column. SQL LIKE Syntax SELECT column_name(s)FROM table_nameWHERE column_name LIKE …[ More ]
SQL TOP Clause
SQL TOP Clause The TOP Clause The TOP clause is used to specify the number of records to return. The TOP clause can be very useful on large tables with thousands of records. Returning a large number of records can impact on performance. Note: Not all database systems support the TOP clau…[ More ]
SQL UPDATE Statement
SQL UPDATE Statement The UPDATE statement is used to update records in a table. The UPDATE Statement The UPDATE statement is used to update existing records in a table. SQL UPDATE Syntax UPDATE table_nameSET column1=value, column2=value2,...WHERE some_column=some_value Note: …[ More ]
SQL INSERT INTO Statement
SQL INSERT INTO Statement The INSERT INTO statement is used to insert new records in a table. The INSERT INTO Statement The INSERT INTO statement is used to insert a new row in a table. SQL INSERT INTO Syntax It is possible to write the INSERT INTO statement in two forms. The firs…[ More ]
SQL ORDER BY Keyword
SQL ORDER BY Keyword The ORDER BY keyword is used to sort the result-set. The ORDER BY Keyword The ORDER BY keyword is used to sort the result-set by a specified column. The ORDER BY keyword sort the records in ascending order by default. If you want to sort the records in a descend…[ More ]
SQL AND & OR Operators
SQL AND & OR Operators The AND & OR operators are used to filter records based on more than one condition. The AND & OR Operators The AND operator displays a record if both the first condition and the second condition is true. The OR operator displays a record if either the first c…[ More ]
SQL WHERE Clause
SQL WHERE Clause The WHERE clause is used to filter records. The WHERE Clause  The WHERE clause is used to extract only those records that fulfill a specified criterion. SQL WHERE Syntax SELECT column_name(s)FROM table_nameWHERE column_name operator value WHERE Clause E…[ More ]
SQL SELECT DISTINCT Statement
SQL SELECT DISTINCT Statement This chapter will explain the SELECT DISTINCT statement. The SQL SELECT DISTINCT Statement In a table, some of the columns may contain duplicate values. This is not a problem, however, sometimes you will want to list only the different (distinct) values…[ More ]
SQL SELECT Statement
SQL SELECT Statement This chapter will explain the SELECT and the SELECT * statements. The SQL SELECT Statement The SELECT statement is used to select data from a database. The result is stored in a result table, called the result-set. SQL SELECT Syntax SELECT column_name(s)F…[ More ]
SQL Syntax
SQL Syntax Database Tables A database most often contains one or more tables. Each table is identified by a name (e.g. "Customers" or "Orders"). Tables contain records (rows) with data. Below is an example of a table called "Persons": P_Id LastName FirstName Address City …[ More ]
Introduction to SQL
Introduction to SQL SQL is a standard language for accessing and manipulating databases. What is SQL? SQL stands for Structured Query Language SQL lets you access and manipulate databases SQL is an ANSI (American National Standards Institute) standard What Can SQL do? SQL c…[ More ]
JavaScript Create Your Own Objects
JavaScript Create Your Own Objects Objects are useful to organize information. Try it Yourself - Examples Create a direct instance of an object Create a template for an object JavaScript Objects Earlier in this tutorial we have seen that JavaScript has several built…[ More ]
JavaScript Timing Events
JavaScript Timing EventsJavaScript Timing EventsWith JavaScript, it is possible to execute some code after a specified time-interval. This is called timing events.It's very easy to time events in JavaScript. The two key methods that are used are:setTimeout() - executes a code some time in the future…[ More ]
JavaScript Image Maps
JavaScript Image Maps An image-map is an image with clickable regions. HTML Image Maps From our HTML tutorial we have learned that an image-map is an image with clickable regions. Normally, each region has an associated hyperlink. Clicking on one of the regions takes you to the asso…[ More ]
Animation
Animation With JavaScript we can create animated images. JavaScript Animation It is possible to use JavaScript to create animated images. The trick is to let a JavaScript change between different images on different events. In the following example we will add an image that should…[ More ]
JavaScript Form Validation
JavaScript Form Validation JavaScript Form Validation JavaScript can be used to validate data in HTML forms before sending off the content to a server. Form data that typically are checked by a JavaScript could be: has the user left required fields empty? has the user entered a valid e…[ More ]
Cookies
Cookies A cookie is often used to identify a user. What is a Cookie? A cookie is a variable that is stored on the visitor's computer. Each time the same computer requests a page with a browser, it will send the cookie too. With JavaScript, you can both create and retrieve cooki…[ More ]
JavaScript Browser Detection
JavaScript Browser Detection The JavaScript Navigator object contains information about the visitor's browser. Browser Detection Almost everything in this tutorial works on all JavaScript-enabled browsers. However, there are some things that just don't work on certain browsers - e…[ More ]