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MariaDBでのSHOWCHARACTERSETのしくみ

    MariaDBでは、SHOW CHARACTER SETを使用できます MariaDBで使用可能なすべての文字セットを返す管理SQLステートメント。

    構文

    構文は次のようになります:

    SHOW CHARACTER SET [LIKE 'pattern' | WHERE expr]

    オプションのLIKEを使用できます および/またはWHERE 結果を絞り込むための句。

    実例をいくつか示します。

    LIKE 条項

    LIKEを使用する例を次に示します。 latinで始まるすべての文字セットを返す句 :

    SHOW CHARACTER SET LIKE 'latin%';

    結果:

    +---------+-----------------------------+-------------------+--------+
    | Charset | Description                 | Default collation | Maxlen |
    +---------+-----------------------------+-------------------+--------+
    | latin1  | cp1252 West European        | latin1_swedish_ci |      1 |
    | latin2  | ISO 8859-2 Central European | latin2_general_ci |      1 |
    | latin5  | ISO 8859-9 Turkish          | latin5_turkish_ci |      1 |
    | latin7  | ISO 8859-13 Baltic          | latin7_general_ci |      1 |
    +---------+-----------------------------+-------------------+--------+

    WHERE 条項

    WHEREを使用する例を次に示します。 Maxlenを持つすべての文字セットを返す句 3の :

    SHOW CHARACTER SET WHERE Maxlen LIKE '3';

    結果:

    +---------+---------------------------+---------------------+--------+
    | Charset | Description               | Default collation   | Maxlen |
    +---------+---------------------------+---------------------+--------+
    | ujis    | EUC-JP Japanese           | ujis_japanese_ci    |      3 |
    | utf8    | UTF-8 Unicode             | utf8_general_ci     |      3 |
    | eucjpms | UJIS for Windows Japanese | eucjpms_japanese_ci |      3 |
    +---------+---------------------------+---------------------+--------+

    AND およびOR キーワード

    条件をANDと組み合わせることができます および/またはOR キーワード:

    SHOW CHARACTER SET 
    WHERE Maxlen LIKE '3'
    OR Description LIKE '%Japanese%';

    結果:

    +---------+---------------------------+---------------------+--------+
    | Charset | Description               | Default collation   | Maxlen |
    +---------+---------------------------+---------------------+--------+
    | ujis    | EUC-JP Japanese           | ujis_japanese_ci    |      3 |
    | sjis    | Shift-JIS Japanese        | sjis_japanese_ci    |      2 |
    | utf8    | UTF-8 Unicode             | utf8_general_ci     |      3 |
    | cp932   | SJIS for Windows Japanese | cp932_japanese_ci   |      2 |
    | eucjpms | UJIS for Windows Japanese | eucjpms_japanese_ci |      3 |
    +---------+---------------------------+---------------------+--------+

    すべての文字セットを返す

    すべての文字セットを返すには、すべての句を削除するだけです。

    SHOW CHARACTER SET;

    結果:

    +----------+-----------------------------+---------------------+--------+
    | Charset  | Description                 | Default collation   | Maxlen |
    +----------+-----------------------------+---------------------+--------+
    | big5     | Big5 Traditional Chinese    | big5_chinese_ci     |      2 |
    | dec8     | DEC West European           | dec8_swedish_ci     |      1 |
    | cp850    | DOS West European           | cp850_general_ci    |      1 |
    | hp8      | HP West European            | hp8_english_ci      |      1 |
    | koi8r    | KOI8-R Relcom Russian       | koi8r_general_ci    |      1 |
    | latin1   | cp1252 West European        | latin1_swedish_ci   |      1 |
    | latin2   | ISO 8859-2 Central European | latin2_general_ci   |      1 |
    | swe7     | 7bit Swedish                | swe7_swedish_ci     |      1 |
    | ascii    | US ASCII                    | ascii_general_ci    |      1 |
    | ujis     | EUC-JP Japanese             | ujis_japanese_ci    |      3 |
    | sjis     | Shift-JIS Japanese          | sjis_japanese_ci    |      2 |
    | hebrew   | ISO 8859-8 Hebrew           | hebrew_general_ci   |      1 |
    | tis620   | TIS620 Thai                 | tis620_thai_ci      |      1 |
    | euckr    | EUC-KR Korean               | euckr_korean_ci     |      2 |
    | koi8u    | KOI8-U Ukrainian            | koi8u_general_ci    |      1 |
    | gb2312   | GB2312 Simplified Chinese   | gb2312_chinese_ci   |      2 |
    | greek    | ISO 8859-7 Greek            | greek_general_ci    |      1 |
    | cp1250   | Windows Central European    | cp1250_general_ci   |      1 |
    | gbk      | GBK Simplified Chinese      | gbk_chinese_ci      |      2 |
    | latin5   | ISO 8859-9 Turkish          | latin5_turkish_ci   |      1 |
    | armscii8 | ARMSCII-8 Armenian          | armscii8_general_ci |      1 |
    | utf8     | UTF-8 Unicode               | utf8_general_ci     |      3 |
    | ucs2     | UCS-2 Unicode               | ucs2_general_ci     |      2 |
    | cp866    | DOS Russian                 | cp866_general_ci    |      1 |
    | keybcs2  | DOS Kamenicky Czech-Slovak  | keybcs2_general_ci  |      1 |
    | macce    | Mac Central European        | macce_general_ci    |      1 |
    | macroman | Mac West European           | macroman_general_ci |      1 |
    | cp852    | DOS Central European        | cp852_general_ci    |      1 |
    | latin7   | ISO 8859-13 Baltic          | latin7_general_ci   |      1 |
    | utf8mb4  | UTF-8 Unicode               | utf8mb4_general_ci  |      4 |
    | cp1251   | Windows Cyrillic            | cp1251_general_ci   |      1 |
    | utf16    | UTF-16 Unicode              | utf16_general_ci    |      4 |
    | utf16le  | UTF-16LE Unicode            | utf16le_general_ci  |      4 |
    | cp1256   | Windows Arabic              | cp1256_general_ci   |      1 |
    | cp1257   | Windows Baltic              | cp1257_general_ci   |      1 |
    | utf32    | UTF-32 Unicode              | utf32_general_ci    |      4 |
    | binary   | Binary pseudo charset       | binary              |      1 |
    | geostd8  | GEOSTD8 Georgian            | geostd8_general_ci  |      1 |
    | cp932    | SJIS for Windows Japanese   | cp932_japanese_ci   |      2 |
    | eucjpms  | UJIS for Windows Japanese   | eucjpms_japanese_ci |      3 |
    +----------+-----------------------------+---------------------+--------+
    40 rows in set (0.001 sec)

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