![]() A database table is similar, in that data is stored in rows and columns. If you’ve ever created a spreadsheet, this will look familiar to you. These rows and columns form a table that’s represented in the image below. Each joke stored in this way would be said to be a row or entry in the table. ![]() In our example, our joke table might have one column for the text of the jokes, and another for the dates on which the jokes were added to the database. Each column holds a certain piece of information about each item in the table. Each table in a database has one or more columns, or fields. For our joke database, we’d probably start with a table called joke that would contain a list of jokes. A database is composed of one or more tables, each of which contains a list of items, or things. Let’s run with this example as we look at how data is stored in a database. The PHP code would take care of the rest, automatically displaying the new joke along with the others when it fetched the list from the database. Second, adding a joke to your website would be a simple matter of inserting the joke into the database. First, instead of writing an HTML page for each joke, you could write a single PHP script designed to fetch any joke from the database and display it by generating an HTML page for it on the fly. The advantage of this approach is twofold. In this example, the jokes would be stored entirely in the database. For example, you could tell PHP to look in the database for a list of jokes that you’d like to appear on your website. In this chapter, we’ll learn what a database is, and how to work with your own databases using Structured Query Language (SQL).Ī database server is a program that can store large amounts of information in an organized format that’s easily accessible through programming languages like PHP. ![]() Now, that’s all well and good, but it really gets interesting when a database is added to the mix. We’ve looked at a few basic examples, including generating random numbers and using forms to capture input from a user. Displaying Data from MySQL on the Web: an IntroductionĪs I explained in the last chapter, PHP is a server-side scripting language that lets you insert instructions into your web pages that your web server software will execute before it sends those pages to browsers that request them.Setting Up Your PHP Development Environment with Docker.In this third tutorial in the series, you’ll learn what a database is, and how to work with your own databases using Structured Query Language (SQL). SQL can set permissions on tables, procedures, and viewsĪlthough SQL is an ANSI/ISO standard, there are different versions of the SQL language.The following article is an excerpt from PHP & MySQL: Novice to Ninja, 7th Edition, a hands-on guide to learning all the tools, principles, and techniques needed to build a professional web application.SQL can create stored procedures in a database.SQL can create new tables in a database.SQL can execute queries against a database.In 1986, and of the International Organization for Standardization (ISO) in SQL became a standard of the American National Standards Institute (ANSI).SQL lets you access and manipulate databases.SQL stands for Structured Query Language.SQL is a standard language for accessing and manipulating databases. String Functions: ASCII CHAR_LENGTH CHARACTER_LENGTH CONCAT CONCAT_WS FIELD FIND_IN_SET FORMAT INSERT INSTR LCASE LEFT LENGTH LOCATE LOWER LPAD LTRIM MID POSITION REPEAT REPLACE REVERSE RIGHT RPAD RTRIM SPACE STRCMP SUBSTR SUBSTRING SUBSTRING_INDEX TRIM UCASE UPPER Numeric Functions: ABS ACOS ASIN ATAN ATAN2 AVG CEIL CEILING COS COT COUNT DEGREES DIV EXP FLOOR GREATEST LEAST LN LOG LOG10 LOG2 MAX MIN MOD PI POW POWER RADIANS RAND ROUND SIGN SIN SQRT SUM TAN TRUNCATE Date Functions: ADDDATE ADDTIME CURDATE CURRENT_DATE CURRENT_TIME CURRENT_TIMESTAMP CURTIME DATE DATEDIFF DATE_ADD DATE_FORMAT DATE_SUB DAY DAYNAME DAYOFMONTH DAYOFWEEK DAYOFYEAR EXTRACT FROM_DAYS HOUR LAST_DAY LOCALTIME LOCALTIMESTAMP MAKEDATE MAKETIME MICROSECOND MINUTE MONTH MONTHNAME NOW PERIOD_ADD PERIOD_DIFF QUARTER SECOND SEC_TO_TIME STR_TO_DATE SUBDATE SUBTIME SYSDATE TIME TIME_FORMAT TIME_TO_SEC TIMEDIFF TIMESTAMP TO_DAYS WEEK WEEKDAY WEEKOFYEAR YEAR YEARWEEK Advanced Functions: BIN BINARY CASE CAST COALESCE CONNECTION_ID CONV CONVERT CURRENT_USER DATABASE IF IFNULL ISNULL LAST_INSERT_ID NULLIF SESSION_USER SYSTEM_USER USER VERSION SQL Server Functions
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