Funções da dbx

Índice

  • dbx_close — Encera uma conexão/banco de dados
  • dbx_compare — Compara duas linhas para finalidades de ordenação
  • dbx_connect — Inicia uma conexão/banco de dados
  • dbx_error — Mostra a mensagem de erro da última função chamada no módulo
  • dbx_escape_string — Transforma uma string para que ela possa ser seguramente usada em comandos-sql.
  • dbx_fetch_row — Lê as linhas do resultado de uma requisição que tem a flag DBX_RESULT_UNBUFFERED ligada
  • dbx_query — Envia uma requisição e armazena todos os resultados (se houver)
  • dbx_sort — Ordena um resultado de uma dbx_query usando uma função
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User Contributed Notes 5 notes

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4
carl [at] carlthompson [dot] net
21 years ago
The above benchmark is very misleading. Unfortunately, I found out the hard way by porting my app to ADODB. Most PHP apps are going to be very short-lived therefore startup / setup time is a large factor. This benchmark does not measure that. Just include()ing the main ADODB file added 27ms to my app's startup time! Considering my app took only 16ms to run in total using DBX, the idea of switching to ADODB was DOA before running a single query.

In the end, the total time for my app went from 16ms with DBX to 49ms with ADODB. ADODB's powerful features are obviously not worth that kind of overhead.

Carl Thompson
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2
bart at mediawave dot nl
20 years ago
Simple function for returning paged result sets.

<?php
// use: pagedQuery($link, $sql, $rows_per_page, $current_page)

function pagedQuery($link, $sql, $nrows = 10, $page = 1) {
   
$handle = dbx_query($link, $sql, DBX_RESULT_UNBUFFERED);
   
$result = new stdClass;
   
$result->link = $this->link;
   
$result->page = $page;
   
$result->data = array();
   
$result->info['name'] = array();
   
$start = ($page - 1) * $nrows;
   
$end = $start + $nrows;
   
$result->rows = 0;
    while (
$row = dbx_fetch_row($handle)) {
       
$result->rows++;
        if ((
$result->rows > $start) && ($result->rows <= $end)) {
           
$result->data[] = $row;           
        }
    }
    if (
$result->data[0]) {
       
$result->cols = count($result->data[0]) / 2;
       
$result->info['name'] = array_slice(array_keys($result->data[0]), $result->cols, $result->cols);
       
$result->lastPage = ceil($result->rows / $nrows);
    }
    return
$result;
}
?>
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0
rhcf at linux dot ime dot usp dot br
21 years ago
BEWARE!!!

dbx_query allocate all retrieved data in an array on memory. If the query result is big (bigger then the memory_limit on php.ini), the result will be empty. So use dbx wih care.
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-3
bart at mediawave dot nl
20 years ago
Would like to confirm that dbx is at least three times faster than adodb with my application. However, once loaded, adodb has much more features and probably performs better in some situations then dbx.

One of the nice features that adodb has, is the way you can quickly make a dropdown menu from a query. Here's a similar function that works with a dbx result object:

<?php

// $result is the dbx_query result (It expects two fields)
// $name is the name of the dropdown field
// $selected is the option that should be selected
// $firstrow takes a string like "myvalue:myname"
// $attr can be used to add some extra attributes

function dropDown($result, $name, $selected, $firstRow, $attr) {
   
$s = '<select name="'.$name.'" '.$attr.'>';
    if (
is_string($firstRow))  {
       
$row = explode(':', $firstRow);
       
$s .= '<option value="'.$row[0].'">'.$row[1].'</option>';
    } else
       
$s .= '<option></option>';
    foreach (
$result->data as $row) {
        if (
$row[0] == $selected)
           
$s .= '<option value="'.$row[0].'" selected="selected">'.htmlspecialchars($row[1]).'</option>';
        else
           
$s .= '<option value="'.$row[0].'">'.htmlspecialchars($row[1]).'</option>';
    }
    return
$s.'</select>';
}

?>
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-3
jlim at natsoft dot com dot my
21 years ago
For some benchmarks of dbx connecting to mysql compared to native mysql api, adodb, and others, see:
http://phplens.com/lens/adodb/
http://php.weblogs.com/2003/02/06#a2336
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