PHP数组到postgres数组

Question

现在PHP不能直接使用Postgresql数组。例如，PHP采取postgresql数组像 '{“foo”，“bar”}'

我需要简单的PHP函数从php数组创建多维postgresql数组。

我认为实验pg_convert（）不是最优的，因为它需要额外的数据来形成数据库输出的简单数组字符串，也许我误解了这个函数的想法。

例如，我需要转换

$from=array( array("par_1_1","par_1_2"), array("array_2_1", "array_2_2") ); 
$to='{{"par_1_1","par_1_2"},{"par_2_1","par_2_2"}}'; 

可否使用array_walk_recursive（）到阵列的最深元素转换？

Answer 1

下面是一个将PHP数组转换为PG数组的简单函数。

function to_pg_array($set) { 
    settype($set, 'array'); // can be called with a scalar or array 
    $result = array(); 
    foreach ($set as $t) { 
     if (is_array($t)) { 
      $result[] = to_pg_array($t); 
     } else { 
      $t = str_replace('"', '\\"', $t); // escape double quote 
      if (! is_numeric($t)) // quote only non-numeric values 
       $t = '"' . $t . '"'; 
      $result[] = $t; 
     } 
    } 
    return '{' . implode(",", $result) . '}'; // format 
} 

Answer 2

JMZ的答案使用字符串数组的额外。

在ARRAY []而不是{}中执行implode。额外：它符合SQL标准。

Answer 3

使用pg_escape_string的报价，并且支持PHP空值和布尔小编辑：

/** 
* Converts a php array into a postgres array (also multidimensional) 
* 
* Each element is escaped using pg_escape_string, only string values 
* are enclosed within single quotes, numeric values no; special 
* elements as php nulls or booleans are literally converted, so the 
* php NULL value is written literally 'NULL' and becomes a postgres 
* NULL (the same thing is done with TRUE and FALSE values). 
* 
* Examples : 
* VARCHAR VERY BASTARD ARRAY : 
* $input = array('bla bla', 'ehi "hello"', 'abc, def', ' \'VERY\' "BASTARD,\'value"', NULL); 
* 
* to_pg_array($input) ==>> 'ARRAY['bla bla','ehi "hello"','abc, def',' ''VERY'' "BASTARD,''value"',NULL]' 
* 
* try to put this value in a query (you will get a valid result): 
* select unnest(ARRAY['bla bla','ehi "hello"','abc, def',' ''VERY'' "BASTARD,''value"',NULL]::varchar[]) 
* 
* NUMERIC ARRAY: 
* $input = array(1, 2, 3, 8.5, null, 7.32); 
* to_pg_array($input) ==>> 'ARRAY[1,2,3,8.5,NULL,7.32]' 
* try: select unnest(ARRAY[1,2,3,8.5,NULL,7.32]::numeric[]) 
* 
* BOOLEAN ARRAY: 
* $input = array(false, true, true, null); 
* to_pg_array($input) ==>> 'ARRAY[FALSE,TRUE,TRUE,NULL]' 
* try: select unnest(ARRAY[FALSE,TRUE,TRUE,NULL]::boolean[]) 
* 
* MULTIDIMENSIONAL ARRAY: 
* $input = array(array('abc', 'def'), array('ghi', 'jkl')); 
* to_pg_array($input) ==>> 'ARRAY[ARRAY['abc','def'],ARRAY['ghi','jkl']]' 
* try: select ARRAY[ARRAY['abc','def'],ARRAY['ghi','jkl']]::varchar[][] 
* 
* EMPTY ARRAY (is different than null!!!): 
* $input = array(); 
* to_pg_array($input) ==>> 'ARRAY[]' 
* try: select unnest(ARRAY[]::varchar[]) 
* 
* NULL VALUE : 
* $input = NULL; 
* to_pg_array($input) ==>> 'NULL' 
* the functions returns a string='NULL' (literally 'NULL'), so putting it 
* in the query, it becomes a postgres null value. 
* 
* If you pass a value that is not an array, the function returns a literal 'NULL'.  
* 
* You should put the result of this functions directly inside a query, 
* without quoting or escaping it and you cannot use this result as parameter 
* of a prepared statement. 
* 
* Example: 
* $q = 'INSERT INTO foo (field1, field_array) VALUES ($1, ' . to_pg_array($php_array) . '::varchar[])'; 
* $params = array('scalar_parameter'); 
* 
* It is recommended to write the array type (ex. varchar[], numeric[], ...) 
* because if the array is empty or contains only null values, postgres 
* can give an error (cannot determine type of an empty array...) 
* 
* The function returns only a syntactically well-formed array, it does not 
* make any logical check, you should consider that postgres gives errors 
* if you mix different types (ex. numeric and text) or different dimensions 
* in a multidim array. 
* 
* @param array $set PHP array 
* 
* @return string Array in postgres syntax 
*/ 
function to_pg_array($set) { 

    if (is_null($set) || !is_array($set)) { 
     return 'NULL'; 
    } 

    // can be called with a scalar or array 
    settype($set, 'array'); 

    $result = array(); 
    foreach ($set as $t) { 
      // Element is array : recursion 
     if (is_array($t)) { 
      $result[] = to_pg_array($t); 
     } 
     else { 
      // PHP NULL 
      if (is_null($t)) { 
       $result[] = 'NULL'; 
      } 
      // PHP TRUE::boolean 
      elseif (is_bool($t) && $t == TRUE) { 
       $result[] = 'TRUE'; 
      } 
      // PHP FALSE::boolean 
      elseif (is_bool($t) && $t == FALSE) { 
       $result[] = 'FALSE'; 
      } 
      // Other scalar value 
      else { 
       // Escape 
       $t = pg_escape_string($t); 

       // quote only non-numeric values 
       if (!is_numeric($t)) { 
        $t = '\'' . $t . '\''; 
       } 
       $result[] = $t; 
      } 
     } 
    } 
    return 'ARRAY[' . implode(",", $result) . ']'; // format 
} 

Answer 4

这是一样的@ mstefano80答案，但更多的人可读，通用和现代的（至少对我来说）：

<?php 

class Sql 
{ 
    /** 
    * Convert PHP-array to SQL-array 
    * https://stackoverflow.com/questions/5631387/php-array-to-postgres-array 
    * 
    * @param array $data 
    * @return string 
    */ 
    public static function toArray(array $data, $escape = 'pg_escape_string') 
    { 
     $result = []; 

     foreach ($data as $element) { 
      if (is_array($element)) { 
       $result[] = static::toArray($element, $escape); 
      } elseif ($element === null) { 
       $result[] = 'NULL'; 
      } elseif ($element === true) { 
       $result[] = 'TRUE'; 
      } elseif ($element === false) { 
       $result[] = 'FALSE'; 
      } elseif (is_numeric($element)) { 
       $result[] = $element; 
      } elseif (is_string($element)) { 
       $result[] = "'" . $escape($element) . "'"; 
      } else { 
       throw new \InvalidArgumentException("Unsupported array item"); 
      } 
     } 

     return sprintf('ARRAY[%s]', implode(',', $result)); 
    } 
} 

测试

<?php 

use Sql; 

class SqlTest extends \PHPUnit_Framework_TestCase 
{ 
    public function testToArray() 
    { 
     $this->assertSame("ARRAY['foo','bar']", Sql::toArray(['foo', 'bar'])); 

     $this->assertSame("ARRAY[1,2]", Sql::toArray([1, 2])); 

     $this->assertSame("ARRAY[1,2]", Sql::toArray(['1', '2'])); 

     $this->assertSame("ARRAY['foo\\\"bar','bar\'foo']", Sql::toArray(['foo"bar', 'bar\'foo'], function($str){ 
      return addslashes($str); 
     })); 

     $this->assertSame("ARRAY[ARRAY['foo\\\"bar'],ARRAY['bar\'foo']]", Sql::toArray([['foo"bar'], ['bar\'foo']], function($str){ 
      return addslashes($str); 
     })); 
    } 
}