php取数组的行数,PHP 从结果中提取所有行作为一个数组

数组的行数,PHP 从结果中提取所有行作为一个数组"/>

php取数组的行数,PHP 从结果中提取所有行作为一个数组

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strata_ranger at hotmail dot com (2009-06-11 08:00:41)

Be aware that pg_fetch_all() is subject to the same limitations as pg_fetch_assoc(), in that if your query returns multiple columns with the same name (or alias) then only the rightmost one will be returned in the associative array, other ones will not.

A simple example:

$res=pg_query("SELECT a.*, b.* -- Fetch all columns from both tables

FROM table1 AS a

LEFT OUTER JOIN table2 as b

USING (column)");$rows=pg_fetch_all($res);?>

In this example, since we're selecting columns via *, if any columns from table2 share the same names as those in table1, they will be the ones returned despite that table2 (as the optional side of an outer join) may return NULL values.

This is not a bug, just a limitation of associative arrays in general, and is easy enough to avoid by structuring your queries carefully and using column aliases to avoid confusion.

prefer_not_to at say dot com (2009-06-02 10:09:14)

For those wondering, this function returns a two-dimentional array, the first dimension being a 0-based indexed array, the second dimension an associative. So you might access the first authors surname using $authors[0]["surname"].

Certainly this is the case in PHP 5.2.9, I can't vouch for other versions though.

viniciusweb at gmail dot com (2005-03-20 18:20:18)

This function returns NULL if the parameter is false.

frig1 at gmx dot at (2005-02-03 08:15:03)

I'm using PHP 5.0.1 and pg_fetch_all and here pg_fetch_all is also not recognized as function

(2003-06-09 17:36:35)

Also for those who are trying to move off oracle, pg_fetch_all returns an array with rows and columns inverted in the sense of ocifetchall. You would need to transpose this result array before your code takes the first index a column name and the second index a row index.

php dot net at mechintosh dot com (2003-05-16 11:42:51)

For versions of PHP that don't yet support the new names or newer functions I wrote a couple functions like this one

if (! function_exists("pg_fetch_all")) {

function pg_fetch_all($res, $kind="assoc") {

$i = 0; // this is needed for the row integer in the looped pg_fetch_array

if ($kind == "assoc") {

while ($row = pg_fetch_array($res, $i, PGSQL_ASSOC)) {

$array_out[] = $row;

$i++;

}else{

while ($row = pg_fetch_array($res)) {

$array_out[] = $row;

}

}

return $array_out;

}

}

tasmanian at devil dot com (2003-03-27 10:42:20)

It seems like pg_fetch_all() only works on version 4.3.x. I tried it with 4.2.2 and it does not recognize the function, so I assume it won't work on 4 => 4.2.x.

jcomeau at whatisthewww dot com (2003-02-19 12:02:26)

pg_fetch_all, despite the app note, accepts only one argument, the resultset. It does exactly what is expected, returning a two-dimensional array of the resultset. I suspect the app note given was just copied from pg_fetch_array, which is what you want to use for a single row.