PHP 8.4.1 Released!

    pg_field_size

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

    pg_field_size — Returns the internal storage size of the named field

    Опис

    pg_field_size(PgSql\Result $result, int $field): int

    pg_field_size() returns the internal storage size (in bytes) of the field number in the given PostgreSQL result.

    Зауваження:

    This function used to be called pg_fieldsize().

    Параметри

    result

    Примірник PgSql\Result, якого повертає одна з функцій pg_query(), pg_query_params() або pg_execute() (серед інших).

    field

    Field number, starting from 0.

    Значення, що повертаються

    The internal field storage size (in bytes). -1 indicates a variable length field.

    Журнал змін

    Версія Опис
    8.1.0 Тепер параметр result має бути примірником PgSql\Result. Раніше очікувався resource.

    Приклади

    Приклад #1 Getting information about fields

    <?php
    $dbconn     = pg_connect("dbname=publisher") or die("Could not connect");

    $res = pg_query($dbconn, "select * from authors where author = 'Orwell'");
    $i = pg_num_fields($res);
    for (    $j = 0; $j < $i; $j++) {
    echo     "column $j\n";
    $fieldname = pg_field_name($res, $j);
    echo     "fieldname: $fieldname\n";
    echo     "printed length: " . pg_field_prtlen($res, $fieldname) . " characters\n";
    echo     "storage length: " . pg_field_size($res, $j) . " bytes\n";
    echo     "field type: " . pg_field_type($res, $j) . " \n\n";
    }
    ?>

    Поданий вище приклад виведе:

    column 0
fieldname: author
printed length: 6 characters
storage length: -1 bytes
field type: varchar 

column 1
fieldname: year
printed length: 4 characters
storage length: 2 bytes
field type: int2 

column 2
fieldname: title
printed length: 24 characters
storage length: -1 bytes
field type: varchar

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    User Contributed Notes 3 notes

    up
    0
    ij at NOSPAM dot irj dot co dot za
    19 years ago
    To view the file structure of a table using a sql query

    select pg_class.relname, pg_attribute.attname, pg_type.typname, pg_type.typlen from pg_class, pg_attribute, pg_type where pg_class.relname = 'YOURTABLENAME' and pg_class.oid = pg_attribute.attrelid and pg_type.oid = pg_attribute.atttypid having attnum > 0
    up
    0
    php at tribun dot de
    19 years ago
    function get_create_syntax( $table )
    {
    $qry = "
    SELECT *
    FROM $table
    LIMIT 1
    ";
    $res = pg_query( $qry );
    $row = pg_fetch_assoc( $res );

    $create = "CREATE TABLE $table \n(\n";

    $item = array();
    for( $i = 0; $i < count( $row ); $i++ )
    {
    $name = pg_field_name( $res, $i );
    $type = pg_field_type( $res, $i );
    $size = pg_field_size( $res, $i );

    $item[$i] = '"'.$name.'" '.$type;

    $qry = "
    SELECT a.atttypmod AS size,
    a.attnotnull AS notnull
    FROM pg_attribute AS a,
    pg_class AS c
    WHERE c.relname = '$table'
    AND a.attrelid = c.oid
    AND a.attname = '$name'
    ";
    $res2 = pg_query( $qry );
    $out = pg_fetch_object( $res2 );

    if( $out -> size != -1 )
    {
    $item[$i] .= '('.( $out -> size - 4 ).')';
    }
    if( $out -> notnull == 't' )
    $item[$i] .= ' NOT';

    $item[$i] .= ' NULL';

    }
    $create .= implode( ",\n", $item ) ."\n);";

    return $create;
    }
    up
    -3
    alex at linuxNOSPAM dot org dot pe
    22 years ago
    How i can extract the struct of a Postgresql Table?

    I want to do a dynamic php code, that see the pg table, and print name, type and size of fields
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