Lesson 2. 0: Retrieve data from a databaseentutorial. Now it's time to retrieve data from our database to our PHP pages. This is really one of the most important lessons in this tutorial. Once you have read and understood this lesson, you will realize why database- driven web solutions are so powerful, and your views on web development will be expanded dramatically. SQL queries. To retrieve data from a database, you use queries. An example of a query could be: "get all data from the table 'people' sorted alphabetically" or "get names from the table 'people'". Again, the language Structured Query Language (SQL) is used to communicate with the database. For those that want an exec that handles params like prepare/execute does. You can simulate this with another function <?php class Real_PDO extends PDO {.Try looking at this simple example. Get all data from the table 'people'. Will be written like this in SQL: The syntax is pretty self- explanatory. Just read on and see how SQL statements are used in the examples below. Example 1: Retrieve data from a table. This example uses the database and table from lesson 1. Therefore, it is important that you read these lessons first. The example shows how data in the table "people" is retrieved with an SQL query. The SQL query returns a result in the form of a series of records. These records are stored in a so- called recordset. A recordset can be described as a kind of table in the server's memory, containing rows of data (records), and each record is subdivided into individual fields (or columns). A recordset can be compared to a table where each record could be compared to a row in the table. In PHP, we can run through a recordset with a loop and the function mysql_fetch_array, which returns each row as an array. The code below shows how to use mysql_fetch_array to loop through a recordset. データベースの書き込みを行います。 まずAndroid SQLiteデータベースを作成するで作成した SQLiteOpenHelperクラスを継承した. Caution (Windows only) When PHP is talking to a SMTP server directly, if a full stop is found on the start of a line, it is removed. To counter-act this. Retrieve data from database < /title>. SQL = "SELECT * FROM people"; $rs = mysql_query($str. SQL); while($row = mysql_fetch_array($rs)) { echo $row['First. Name'] . "< br /> "; }mysql_close(); ?>. Notice that for every record how we get the content of the column "First. Name" by typing $row['First. Name']. Similarly, we can get the content of the column "Phone" by writing $row['Phone'], for example. The order of the recordset is exactly the same as in the table in the database. But in the next example, it will be shown how to sort recordset. Example 2: Sort the data alphabetically, chronologically or numerically. Often it can be helpful if a list or table of data is presented alphabetically, chronologically or numerically. Such sorting is very easy to do with SQL, where the syntax Order By Column. Name is used to sort according to the column contents. Look at the SQL statement from the example above: str. SQL = "SELECT * FROM people"The records can, for example, be sorted alphabetically by the first name of the people this way: str. The UPSERT operation either updates or inserts a row in a table, depending if the table already has a row that matches the data: if table t has a row exists that has. SQL = "SELECT * FROM people ORDER BY First. Name"Or chronologically by date of birth like this: str. SQL = "SELECT * FROM people ORDER BY Birth. Date"The sorting can be charged from ascending to descending by adding DESC: str. SQL = "SELECT * FROM people ORDER BY Birth. Date DESC"In the following example, the people are sorted by age. Retrieve data from database < /title>. SQL = "SELECT * FROM people ORDER BY Birth. Date DESC"; $rs = mysql_query($str. SQL); while($row = mysql_fetch_array($rs)) { echo $row['First. Name'] . " " . $row['Birth. Date'] . "< br /> "; }mysql_close(); ?>. Try to change the SQL statement yourself and sort the records by first name, last name or phone number. Retrieve selected data. Until now, our SQL statement retrieves all rows from the table. But often you need to set criteria in the SQL query for the data to be retrieved, for instance, if we only want the rows for those who have a particular phone number or a certain last name. Say, we only want to retrieve people from the database who have the phone number "6. That could be done like this: str. SQL = "SELECT * FROM people WHERE Phone = '6. There are six relational operators in SQL: = Equals< Less than> Greater Than< = Less than or equal to> = Greater than or equal to!= Not equal to. In addition, there are some logical operators: ANDORNOTSee lesson 6 for more information on how to set up conditions. In the next example, we use conditions to set up an address book. Example 3: Address book. In this example, we will try to combine many of the things you have just learned. We will make a list of the names from the database where each name is a link to further details about the person. For this, we need two files - list. The code of list. Retrieve data from the database< /title>. SQL = "SELECT * FROM people ORDER BY First. Name DESC"; $rs = mysql_query($str. SQL); while($row = mysql_fetch_array($rs)) { $str. Name = $row['First. Name'] . " " . $row['Last. Name']; $str. Link = "< a href = 'person. Navn . "< /a> "; echo "< li> " . Link . "< /li> "; }mysql_close(); ?>. The code for person. Retrieve data from database< /title>. SQL = "SELECT * FROM people WHERE id=" . GET["id"]; $rs = mysql_query($str. SQL); while($row = mysql_fetch_array($rs)) { echo "< dt> Name: < /dt> < dd> " . First. Name"] . " " . Last. Name"] . "< /dd> "; echo "< dt> Phone: < /dt> < dd> " . Phone"] . "< /dd> "; echo "< dt> Birthdate: < /dt> < dd> " . Birth. Date"] . "< /dd> "; }mysql_close(); ?>. Return to the list< /a> < /p>. The address book example is rather simple, but it shows the potential of working with PHP and databases. Imagine that the database had contained 1. By making a few changes in the above files, you could easily create a product catalogue with more than 1. PHP files. Welcome to a world with extensive websites that are easy to develop and maintain! Once you've learned to work with databases, your web solutions will never be the same again.+ Post a new topic< < Lesson 1. Insert data into a database. Lesson 2. 1: Delete data from a database > >. How to Insert JSON Data into My. SQL using PHPHi, in this PHP TUTORIAL, we'll see How to insert JSON Data into My. SQL using PHP. Check out its reverse process of Converting Data from My. SQL to JSON Format in PHP here. Converting json to mysql using php includes several steps and you will learn things like how to read json file, convert json to array and insert that json array into mysql database in this tutorial. For those who wonder what is JSON, let me give a brief introduction. What is JSON File Format? JSON file contains information stored in JSON format and has the extension of "*. JSON stands for Java. Script Object Notation and is a light weight data exchange format. Being less cluttered and more readable than XML, it has become an easy alternative format to store and exchange data. All modern browsers supports JSON format. Example of a JSON File. Read Also: Do you want to know how a JSON file looks like? Well here is the sample. As you can see by yourself, the JSON format is very human readable and the above file contains some employee details. I'm going to use this file as an example for this tutorial and show you how to insert this JSON object into My. SQL database in PHP step by step. Step 1: Connect PHP to My. SQL Database. As the first and foremost step we have to connect PHP to the My. SQL database in order to insert JSON data into My. SQL DB. For that we use mysql_connect() function to connect PHP with My. SQL. $con = mysql_connect("username","password","") or die('Could not connect: ' . Here "employee" is the My. SQL Database name we want to store the JSON object. Learn more about using mysqli library for php and mysql database connection here. Step 2: Read the JSON file in PHPNext we have to read the JSON file and store its contents to a PHP variable. But how to read json file in php? Well! PHP supports the function file_get_contents() which will read an entire file and returns it as a string. Let’s use it to read our JSON file. Here "empdetails. JSON file name we want to read. Step 3: Convert JSON String into PHP Array. The next step for us is to convert json to array. Which is likely we have to convert the JSON string we got from the above step to PHP associative array. Again we use the PHP json decode function which decodes JSON string into PHP array. The first parameter $jsondata contains the JSON file contents. The second parameter true will convert the string into php associative array. Step 4: Extract the Array Values. Next we have to parse the above JSON array element one by one and store them into PHP variables. Step 5: Insert JSON to My. SQL Database with PHP Code. Using the above steps, we have extracted all the values from the JSON file. Finally let's insert the extracted JSON object values into the My. SQL table. //insert into mysql table. INSERT INTO tbl_emp(empid, empname, gender, age, streetaddress, city, state, postalcode, designation, department). VALUES('$id', '$name', '$gender', '$age', '$streetaddress', '$city', '$state', '$postalcode', '$designation', '$department')". Error : ' . mysql_error()). We are done!!! Now we have successfully imported JSON data into My. SQL database. Here is the complete php code snippet I have used to insert JSON to My. SQL using PHP. Complete PHP Script. Could not connect: ' . INSERT INTO tbl_emp(empid, empname, gender, age, streetaddress, city, state, postalcode, designation, department). VALUES('$id', '$name', '$gender', '$age', '$streetaddress', '$city', '$state', '$postalcode', '$designation', '$department')". Error : ' . mysql_error()). SJ0. 11. MS". "personal": {. Smith Jones". "gender": "Male". Street". "city": "New York". NY". "postalcode": "1. Deputy General". "department": "Finance". Read: Hope this tutorial helps you to understand how to insert JSON data into My. SQL using PHP. Last Modified: Feb- 2.
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