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pg_num_rows

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

pg_num_rowsReturns the number of rows in a result

Descrição

pg_num_rows(PgSql\Result $result): int

pg_num_rows() will return the number of rows in an PgSql\Result instance.

Nota:

This function used to be called pg_numrows().

Parâmetros

result

Uma instância de PgSql\Result, retornada por pg_query(), pg_query_params() ou pg_execute() (entre outras).

Valor Retornado

The number of rows in the result. On error, -1 is returned.

Registro de Alterações

Versão Descrição
8.1.0 O parâmetro result agora espera uma instância de PgSql\Result; anteriormente, um resource era esperado.

Exemplos

Exemplo #1 pg_num_rows() example

<?php
$result
= pg_query($conn, "SELECT 1");

$rows = pg_num_rows($result);

echo
$rows . " row(s) returned.\n";
?>

O exemplo acima produzirá:

1 row(s) returned.

Veja Também

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User Contributed Notes 3 notes

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4
strata_ranger at hotmail dot com
14 years ago
As mentioned, if you are performing an INSERT/UPDATE or DELETE query and want to know the # of rows affected, you should use pg_affected_rows() instead of pg_num_rows().

However, you can also exploit postgres's RETURNING clause in your query to auto-select columns from the affected rows. This has the advantage of being able to tell not only how many rows a query affects, but exactly which rows those were, especially if you return a primary-key column.

For example:

<?php

// Example query. Let's say that this updates five rows in the source table.
$res = pg_query("Update foo set bar = 'new data' where foo.bar = 'old data' ");
pg_num_rows($res); // 0
pg_affected_rows($res); // 5
pg_fetch_all($res); // FALSE

// Same query, with a RETURNING clause.
$res = pg_query("Update foo set bar = 'new data' where foo.bar = 'old data' RETURNING foo.pkey");
pg_num_rows($res); // 5
pg_affected_rows($res); // 5
pg_fetch_all($res); // Multidimensional array corresponding to our affected rows & returned columns
?>
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1
francisco at natserv dot com
16 years ago
Not sure why this documentation doesn't have the following note:
Note: Use pg_affected_rows() to get number of rows affected by INSERT, UPDATE and DELETE query.

Found on other resources. Adding here in case someone else is looking for the info.
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0
ElDiablo
15 years ago
About preceding note, you shouldn't use pg_num_rows() for this.
You should have instead a look at pg_affected_rows().
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