pg_fetch_result

(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)

pg_fetch_result — Retorna valores a partir de um recurso (resource) de resultado

Descrição

pg_fetch_result ( resource $result , int $row , mixed $field ) : misto

pg_fetch_result() retorna valores a partir de um recurso (resource) de resultado result criado por pg_query(). row é um inteiro. field é um nome de campo (string) ou um índice de campo (inteiro). row e field especificam que célula da tabela deve ser recuperada. A numeração de linhas começa de 0. Ao invés de nomear o campo, você pode usar o índice numérico de campo sem aspas. Índices de campo iniciam-se em 0.

PostgreSQL tem muitos tipos internos mas apenas os tipos básicos são suportados. Todas as formas de tipo integer são retornadas como valores integer. Todas as formas de tipos reais (ponto flutuante) são retornados como valores float. Boolean é retornado como "t" ou "f". Todos os outros tipos, incluindo arrays, são retornados como strings formatadas na mesma maneira padrão que o PostgreSQL retornaria com o programa psql.

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User Contributed Notes 5 notes

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ElDiablo ¶

5 years ago


Please note that a very old bug (#76548) has been fixed in 7.2.8.

Previously, pg_fetch_result did not fetch the next row if $row was omitted.
It is now well the case, so bad use of the function can now cause some bugs in your codes.

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newby_AT_nobletec_DOT_com ¶

21 years ago


Comment on boolean fields:

If you retrieve a boolean value from the PostgreSQL database, be aware that the value returned will be either the character 't' or the character 'f', not an integer.  So, the statement

     if (pg_fetch_result($rsRecords,0,'blnTrueFalseField')) {
       echo "TRUE";
     } else {
       echo "FALSE";
     }

will echo "TRUE" in either case (True or False stored in the field).  In order to work as expected, do this instead:

     if (pg_fetch_result($rsRecords,0,'blnTrueFalseField') == 't') {
       echo "TRUE";
     } else {
       echo "FALSE";
     }

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Alan U. Kennington ¶

17 years ago


See bug #33809 http://bugs.php.net/bug.php?id=33809
Whether this really is a bug or a feature is not clear.
However, it is probably best to always put your column names in extra quotes.

$res = pg_query(...);
$colname = pg_field_name($res, $j);
pg_fetch_result($res, $i, "\"$colname\"");

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-1

Alan U Kennington ¶

17 years ago


In order to use upper case in pg_fetch_result column names, it is apparently necessary to include explicit quotation marks.

Thus when I do this sort of thing:

$res = pg_query(...);
$ncols = pg_num_fields($res);
for ($j = 0; $j < $ncols; ++$j) {
    $colname[$j] = pg_field_name($res, $j);
    $name = htmlspecialchars($colname[$j]);
    print("Column $j name = \"$name\"\n");
    $value = htmlspecialchars(pg_fetch_result($res, 0, $colname[$j]));
    print("Column \"{$colname[$j]}\" value = \"$value\"\n");
    }

I get this sort of thing:

[....]
Warning: pg_fetch_result() [function.pg-fetch-result]: Bad column offset specified in /.../view.php on line 247
Column 8 name = "VEC index"
Column "VEC index" value = ""

But if I change the $value line to this:

$value = htmlspecialchars(pg_fetch_result($res, 0, "\"$colname[$j]\""));

I get this:

[...]
Column 8 name = "VEC index"
Column "VEC index" value[0] = "47"

In my opinion, pg_fetch_result(...) should use the quotes already. In other words, this may be a bug in the PHP postgres library. It does not seem to be a documented feature of pg_fetch_result() although the postgresql manual documents it under "SQL syntax", "Lexical structure".

PHP version 5.1.4.
psql version 8.1.4.

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-2

Akbar ¶

19 years ago


Use can use pg_fetch_result when getting a value (like a smallint as in this example) returned by your stored procedure 

<?php
$pgConnection = pg_connect("dbname=users user=me");

$userNameToCheckFor = "metal";

$result = pg_query($pgConnection, "SELECT howManyUsersHaveThisName('$userNameToCheckFor')");

$count = pg_fetch_result($result, 0, 'howManyUsersHaveThisName');

?>

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