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How to correctly understand the PHP function to obtain and display database data_PHP Tutorial
How to correctly understand the PHP function to obtain and display database data_PHP Tutorial
Using
PHP to get and display database data function mysql_result()
mixed mysql_result(resource result_set, int row [,mixed field])
Get the data of a field from the specified row of result_set. Simple but inefficient.
Example:
- $ link1 = @mysql_connect("server1",
"webuser", "password") - or die("Could not connect
to mysql server!"); - @mysql_select_db("company")
or die("Could not select database !"); -
$query = "select id, name
from product order by name"; 🎜> = - mysql_query($query); $id =
- mysql_result($result, 0, "id"); $name =
- mysql_result($result, 0, "name "); mysql_close(); Note that the above code only outputs the field value of the first piece of data in the result set. If you want Outputting all records requires loop processing. Note that if the query field name is an alias, the alias will be used in mysql_result.
- Mysql_fetch_row, a function of PHP to obtain and display database data ()
Get the entire row from result_set and put the data into the array.
Example (note the clever combination with list):<ol class="dp-xml"><li class="alt"><span><span>for ($</span><span class="attribute">i</span><span> = </span><span class="attribute-value">0</span><span>; $i </span><span class="tag"><</span><span>= mysql_num_rows($result); $i++) </span></span></li><li><span>{ </span></li><li class="alt"><span>$</span><span class="attribute">id</span><span> = </span><span class="attribute-value">mysql_result</span><span>($result, 0, "id"); </span></li><li><span>$</span><span class="attribute">name</span><span> = </span><span class="attribute-value">mysql_result</span><span>($result, 0, "name"); </span></li><li class="alt"><span>echo "Product: $name ($id)"; </span></li><li><span>} </span></li></ol>PHP gets and displays database data function mysql_fetch_array()
array mysql_fetch_array(resource result_set [,int result_type])
Enhancement of mysql_fetch_row() version.
Get each row of result_set as an associative array or/and a numerical index array.
Get two arrays by default, result_type can be set:
<ol class="dp-xml">
<li class="alt"><span><span>$</span><span class="attribute">query</span><span> = </span><span class="attribute-value">"select id, <br>name from product order by name"</span><span>; </span></span></li>
<li>
<span>$</span><span class="attribute">result</span><span> = </span><span class="attribute-value">mysql_query</span><span>($query); </span>
</li>
<li class="alt"><span>while(list($id, $name) <br>= mysql_fetch_row($result)) { </span></li>
<li><span>echo "Product: $name ($id)"; </span></li>
<li class="alt"><span>} </span></li>
</ol>MYSQL_BOTH: Gets two arrays. Therefore, each field can be referenced by index offset or by field name.Example:
PHP gets and displays database data function mysql_fetch_assoc()
array mysql_fetch_assoc(resource result_set)
<ol class="dp-xml">
<li class="alt"><span><span>$</span><span class="attribute">query</span><span> = </span><span class="attribute-value">"select id,<br> name from product order by name"</span><span>; </span></span></li>
<li>
<span>$</span><span class="attribute">result</span><span> = </span><span class="attribute-value">mysql_query</span><span>($query); </span>
</li>
<li class="alt">
<span>while($</span><span class="attribute">row</span><span> = </span><span class="attribute-value">mysql_fetch_array<br></span><span>($result, MYSQL_BOTH)) { </span>
</li>
<li>
<span>$</span><span class="attribute">name</span><span> = $row['name'];</span>
</li>
<li>
<span>//或者 $</span><span class="attribute">name</span><span> = $row[1]; </span>
</li>
<li class="alt">
<span>$</span><span class="attribute">name</span><span> = $row['id'];</span>
</li>
<li class="alt">
<span>//或者 $</span><span class="attribute">name</span><span> = $row[0]; </span>
</li>
<li><span>echo "Product: $name ($id)"; </span></li>
<li class="alt"><span>} </span></li>
</ol>object mysql_fetch_object(resource result_set) It has the same function as mysql_fetch_array(), but it returns not an array, but It is an object.
Example:
The above functions are a summary of PHP's functions for obtaining and displaying database data.
http://www.bkjia.com/PHPjc/446138.html
<ol class="dp-xml">
<li class="alt"><span><span>$</span><span class="attribute">query</span><span> = </span><span class="attribute-value">"select id, name <br>from product order by name"</span><span>; </span></span></li>
<li>
<span>$</span><span class="attribute">result</span><span> = </span><span class="attribute-value">mysql_query</span><span>($query); </span>
</li>
<li class="alt">
<span>while($</span><span class="attribute">row</span><span> = </span><span class="attribute-value">mysql_fetch_object<br></span><span>($result)) { </span>
</li>
<li>
<span>$</span><span class="attribute">name</span><span> = $row-</span><span class="tag">></span><span>name; </span>
</li>
<li class="alt">
<span>$</span><span class="attribute">name</span><span> = $row-</span><span class="tag">></span><span>id; </span>
</li>
<li><span>echo "Product: $name ($id)"; </span></li>
<li class="alt"><span>} </span></li>
</ol>true
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