PHP Classes

File: Sql_Compiler/Sql_CompilerFlow.class.php

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  Classes of Tom Schaefer   SQL Parse and Compile   Sql_Compiler/Sql_CompilerFlow.class.php   Download  
File: Sql_Compiler/Sql_CompilerFlow.class.php
Role: Class source
Content type: text/plain
Description: compile flow control functions
Class: SQL Parse and Compile
Parse and compose SQL queries programatically
Author: By
Last change:
Date: 15 years ago
Size: 3,300 bytes
 

Contents

Class file image Download
<?php

class Sql_CompilerFlow {

   
/**
     * compileControlFlow
     * @desc redirects to different control flow functions
     * @param string $name name of control flow function
     * @param array $tree
     * @param bool $recursing optional
     */
   
public static function doCompile($name, $tree, $recursing) {
        return
call_user_func(array(__CLASS__,"compile".$name),$tree, $recursing);
    }
   
   
/**
     * compileCASE
     * @desc compiles nested case control flow sets
     * => control flow function CASE
     * @param array $tree
     * @param bool $recursing
     * @return string
     */
   
private function compileCASE($tree, $recursing=false){

        if(isset(
$tree["Function"])) {
           
// if it is a nested function then recurse
           
$column = self::doCompile($tree["Function"]["Name"],$tree["Function"], true);
        }
        elseif(isset(
$tree["Name"]))
        {

            if(
is_array($tree["Arg"])) {
               
$column = $tree["Name"] . " "; // function name
               
foreach($tree["Arg"] as $index => $value) {
                    switch(
$value["Type"])
                    {
                        case
'real_val':
                        case
'int_val':
                        case
'null':
                        case
'ident':
                           
$column .= $value["Value"]." ";
                            break;
                        case
'flowcontrol':
                           
$column .= strtoupper($value["Value"])." ";
                            break;
                        case
'text_val':
                           
$column .= $value["Value"]." ";
                            break;
                        case
'Subclause':
                           
$column .= Sql_Compiler::OPENBRACE
                                   
. $this->reCompile($value["Subclause"])
                                    .
Sql_Compiler::CLOSEBRACE." "
                                   
;
                            break;
                    }
                }
               
$column .= "END ";
            }
        }
        return
$column;
    }
   
   
/**
     * compileIF
     * @desc compiles nested if control flow sets
     * => control flow function IF
     * @param array $tree
     * @param bool $recursing
     * @return string
     */
   
private static function compileIF($tree, $recursing=false){
       
        if(isset(
$tree["Function"])) {
           
// if it is a nested function then recurse
           
$column = self::doCompile($tree["Function"]["Name"],$tree["Function"], true);
        }
        elseif(isset(
$tree["Name"]))
        {
            if(
is_array($tree["Arg"])) {
               
$column = $tree["Name"] . Sql_Compiler::OPENBRACE; // function name
               
$implosion = implode (Sql_Compiler::COMMA, $tree);
                if(
strstr(strtolower($implosion),'array')) { // check on error
                   
$funcTree = array();
                    foreach(
$tree["Arg"] as $index => $value){
                        if(
count($value)==1){
                           
$valueNode = $value[0];
                        }
                        if(
is_array($valueNode) && isset($valueNode["Function"]) && isset($valueNode["Function"]["Name"])) {
                           
$funcTree[] = self::doCompile($valueNode["Function"]["Name"], $valueNode, true);
                        } else {
                            if(
is_array($value)) {
                               
$funcTree[] = implode("", $value);
                            } else {
                               
$funcTree[] = $value;
                            }
                        }
                    }
                   
$column .= implode(Sql_Compiler::COMMA, $funcTree);
                } else {
                   
$column .= $implosion;
                }
               
$column .= Sql_Compiler::CLOSEBRACE;
            }
           
           
// only top most function shall have an alias
           
if (empty($recursing) and $tree['Alias'] != '') {
               
$column .= Sql_Compiler::ALIAS . $tree['Alias'];
            }
        }
        return
$column;
    }

   
    public function
compile($name, $tree, $recursing=false){
        return
self::doCompile($name,$tree, $recursing);
    }

}