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    oci_field_scale

    (PHP 5, PHP 7, PHP 8, PECL OCI8 >= 1.1.0)

    oci_field_scale — フィールドの桁数を問い合わせる

    説明

    oci_field_scale(resource $statement, string|int $column): int|false

    column に対応するカラムの桁数を返します。

    FLOAT 型カラムの精度は 0 でなく桁数は -127 となります。 もし精度が 0 の場合、カラムは NUMBER 型、そうでなければ NUMBER(精度, 桁数) となります。

    パラメータ

    statement

    有効な OCI ステートメント ID。

    column

    フィールド番号 (1 から始まる) あるいは名前のいずれか。

    戻り値

    桁数を表す整数値を返します。 失敗した場合に false を返します

    例

    例1 oci_field_scale() の例

    <?php

    // 以下のテーブルを用意します
    // CREATE TABLE mytab (c1 NUMBER, c2 FLOAT, c3 NUMBER(4), c4 NUMBER(5,3));

    $conn = oci_connect("hr", "hrpwd", "localhost/XE");
    if (!    $conn) {
    $m = oci_error();
    trigger_error(htmlentities($m['message']), E_USER_ERROR);
    }

    $stid = oci_parse($conn, "SELECT * FROM mytab");
    oci_execute($stid, OCI_DESCRIBE_ONLY); // 行をフェッチしない場合は OCI_DESCRIBE_ONLY を使います

    $ncols = oci_num_fields($stid);
    for (    $i = 1; $i <= $ncols; $i++) {
    echo     oci_field_name($stid, $i) . " "
    . oci_field_precision($stid, $i) . " "
    . oci_field_scale($stid, $i) . "<br>\n";
    }

    // 出力は
    // C1 0 -127
    // C2 126 -127
    // C3 4 0
    // C4 5 3

    oci_free_statement($stid);
    oci_close($conn);

    ?>

    参考

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    User Contributed Notes 1 note

    up
    1
    VLroyrenn
    6 years ago
    If you're converting SQL values to their respective float and int values based on scale and precision like I am, there's a catch, here.

    This is a slimmed-down version of the conversion logic I'm using :

    <?php
    $col     = [
    'id' => $field_id,
    'name' => oci_field_name($statement, $field_id),
    'type' => oci_field_type($statement, $field_id),
    'scale' => oci_field_scale($statement, $field_id);
    'precision' => oci_field_precision($statement, $field_id);
    ]

    $str_data = oci_result($statement, $field_id)

    switch(    $col['type']) {
    case     'NUMBER':
    if (    $col['precision'] !== 0 && $col['scale'] === -127) {
    // A binary float
    $data = floatval($str_data);
    } else if(    $col['scale'] === 0) {
    // An integer
    $data = intval($str_data);
    } else {
    // A fixed-point decimal number, which has no equivalent in PHP, so float
    $data = floatval($str_data);
    }

    break;

    default:
    $data = $str_data;
    break;
    }

    echo(    "{$col['name']} : $str_data ({$col['type']} ({$col['precision']}, {$col['scale']})) -> $data\n");
    ?>

    What the doc doesn't say is that any number column that was defined without a scale parameter counts as a plain NUMBER(), which always has a precision of 0 and a scale of -127, so they get interpreted as floats even when they should be integers.

    What the doc also doesn't say is that __all analytics functions that return numbers return a plain NUMBER()__, so something like COUNT(*), RANK() or FIRST_VALUE(foo) is still going to net you a float.

    Be careful with these if you have any type-sensitive code that relies on those values (I'm personally very fond of using type-hinting and strict_types = 1).
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