# 24.3. 字元集支援 PostgreSQL 中的字元集支援允許您將文字以各種字元集（也稱為編碼）儲存，包括單位元組字元集（如 ISO 8859 系列）和多位元組字元集，如 EUC（延伸 Unix 代碼）， UTF-8 和 Mule 內部代碼。用戶端可以透通地使用所有支援的字元集，但有一些並不支援在伺服器中使用（即作為伺服器端編碼）。使用 initdb 初始化 PostgreSQL 資料庫叢集時，會選擇預設字元集。建立資料庫時可以覆寫它，因此您可以擁有多個資料庫，每個資料庫具有不同的字元集。 但是，一個重要的限制是每個資料庫的字元集必須與資料庫的 LC\_CTYPE（字元分類）和 LC\_COLLATE（字串排序順序）語言環境設定相容。對於 C 或 POSIX 語言環境，允許使用任何字元集，但對於其他 libc 提供的語言環境，只有一個字元集可以正常工作。（但在 Windows 上，UTF-8 編碼可以與任何語言環境一起使用。）如果您配置了 ICU 支援，ICU 提供的語言環境可以與大多數但不是所有伺服器端編碼一起使用。 ## 24.3.1. 支援的字元集 [Table 24.1](#table-23-1-postgresql-character-sets) 顯示了可在 PostgreSQL 中使用的字元集。 #### **Table 24.1. PostgreSQL Character Sets** | Name | Description | Language | Server? | ICU? | Bytes/Char | Aliases | | ---------------- | --------------------------------- | ------------------------------ | ------- | ---- | ---------- | --------------------------------------------- | | `BIG5` | Big Five | Traditional Chinese | No | No | 1-2 | `WIN950`, `Windows950` | | `EUC_CN` | Extended UNIX Code-CN | Simplified Chinese | Yes | Yes | 1-3 | | | `EUC_JP` | Extended UNIX Code-JP | Japanese | Yes | Yes | 1-3 | | | `EUC_JIS_2004` | Extended UNIX Code-JP, JIS X 0213 | Japanese | Yes | No | 1-3 | | | `EUC_KR` | Extended UNIX Code-KR | Korean | Yes | Yes | 1-3 | | | `EUC_TW` | Extended UNIX Code-TW | Traditional Chinese, Taiwanese | Yes | Yes | 1-3 | | | `GB18030` | National Standard | Chinese | No | No | 1-4 | | | `GBK` | Extended National Standard | Simplified Chinese | No | No | 1-2 | `WIN936`, `Windows936` | | `ISO_8859_5` | ISO 8859-5, ECMA 113 | Latin/Cyrillic | Yes | Yes | 1 | | | `ISO_8859_6` | ISO 8859-6, ECMA 114 | Latin/Arabic | Yes | Yes | 1 | | | `ISO_8859_7` | ISO 8859-7, ECMA 118 | Latin/Greek | Yes | Yes | 1 | | | `ISO_8859_8` | ISO 8859-8, ECMA 121 | Latin/Hebrew | Yes | Yes | 1 | | | `JOHAB` | JOHAB | Korean (Hangul) | No | No | 1-3 | | | `KOI8R` | KOI8-R | Cyrillic (Russian) | Yes | Yes | 1 | `KOI8` | | `KOI8U` | KOI8-U | Cyrillic (Ukrainian) | Yes | Yes | 1 | | | `LATIN1` | ISO 8859-1, ECMA 94 | Western European | Yes | Yes | 1 | `ISO88591` | | `LATIN2` | ISO 8859-2, ECMA 94 | Central European | Yes | Yes | 1 | `ISO88592` | | `LATIN3` | ISO 8859-3, ECMA 94 | South European | Yes | Yes | 1 | `ISO88593` | | `LATIN4` | ISO 8859-4, ECMA 94 | North European | Yes | Yes | 1 | `ISO88594` | | `LATIN5` | ISO 8859-9, ECMA 128 | Turkish | Yes | Yes | 1 | `ISO88599` | | `LATIN6` | ISO 8859-10, ECMA 144 | Nordic | Yes | Yes | 1 | `ISO885910` | | `LATIN7` | ISO 8859-13 | Baltic | Yes | Yes | 1 | `ISO885913` | | `LATIN8` | ISO 8859-14 | Celtic | Yes | Yes | 1 | `ISO885914` | | `LATIN9` | ISO 8859-15 | LATIN1 with Euro and accents | Yes | Yes | 1 | `ISO885915` | | `LATIN10` | ISO 8859-16, ASRO SR 14111 | Romanian | Yes | No | 1 | `ISO885916` | | `MULE_INTERNAL` | Mule internal code | Multilingual Emacs | Yes | No | 1-4 | | | `SJIS` | Shift JIS | Japanese | No | No | 1-2 | `Mskanji`, `ShiftJIS`, `WIN932`, `Windows932` | | `SHIFT_JIS_2004` | Shift JIS, JIS X 0213 | Japanese | No | No | 1-2 | | | `SQL_ASCII` | unspecified (see text) | *any* | Yes | No | 1 | | | `UHC` | Unified Hangul Code | Korean | No | No | 1-2 | `WIN949`, `Windows949` | | `UTF8` | Unicode, 8-bit | *all* | Yes | Yes | 1-4 | `Unicode` | | `WIN866` | Windows CP866 | Cyrillic | Yes | Yes | 1 | `ALT` | | `WIN874` | Windows CP874 | Thai | Yes | No | 1 | | | `WIN1250` | Windows CP1250 | Central European | Yes | Yes | 1 | | | `WIN1251` | Windows CP1251 | Cyrillic | Yes | Yes | 1 | `WIN` | | `WIN1252` | Windows CP1252 | Western European | Yes | Yes | 1 | | | `WIN1253` | Windows CP1253 | Greek | Yes | Yes | 1 | | | `WIN1254` | Windows CP1254 | Turkish | Yes | Yes | 1 | | | `WIN1255` | Windows CP1255 | Hebrew | Yes | Yes | 1 | | | `WIN1256` | Windows CP1256 | Arabic | Yes | Yes | 1 | | | `WIN1257` | Windows CP1257 | Baltic | Yes | Yes | 1 | | | `WIN1258` | Windows CP1258 | Vietnamese | Yes | Yes | 1 | `ABC`, `TCVN`, `TCVN5712`, `VSCII` | 並非所有用戶端 API 都支援所有列出的字元集。例如，PostgreSQL JDBC 驅動程式就不支援 MULE\_INTERNAL，LATIN6，LATIN8 和 LATIN10。 SQL\_ASCII 設定與其他設定的行為大不相同。當伺服器字元集是 SQL\_ASCII 時，伺服器根據 ASCII 標準解譯位元組值 0-127，而位元組值 128-255 作為未解譯的字元。當設定為 SQL\_ASCII 時，不會進行編碼轉換。因此，這個設定並不是使用特定編碼的宣告，而是對編碼的未知宣告。在大多數情況下，如果您使用任何非 ASCII 資料，使用 SQL\_ASCII 設定是不明智的，因為 PostgreSQL 將無法透過轉換或驗證非 ASCII 字元來幫助您。 ## 24.3.2. 設定字元集 initdb 定義 PostgreSQL 叢集的預設字元集（編碼）。例如， ``` initdb -E EUC_JP ``` 將預設字元集設定為 EUC\_JP（日本語的延伸 Unix 代碼）。如果您喜歡更長的選項字串，則可以使用 --encoding 而不是 -E。如果使用 -E 或 --encoding 選項，initdb 將嘗試根據指定的或預設的語言環境決定要使用的相對應編碼。 您可以在資料庫建立時指定非預設編碼，前提是該編碼與所選語言環境相容： ``` createdb -E EUC_KR -T template0 --lc-collate=ko_KR.euckr --lc-ctype=ko_KR.euckr korean ``` 這將建立一個名為 korean 的資料庫，該資料庫使用字元集 EUC\_KR 和語言環境 ko\_KR。另一種方法是使用此 SQL 指令： ``` CREATE DATABASE korean WITH ENCODING 'EUC_KR' LC_COLLATE='ko_KR.euckr' LC_CTYPE='ko_KR.euckr' TEMPLATE=template0; ``` 請注意，上述指令指定複製 template0 資料庫。複製任何其他資料庫時，無法更改原資料庫的編碼和語言環境設定，因為這可能會導致資料損壞。有關更多訊息，請參閱[第 22.3 節](https://docs.postgresql.tw/15/server-administration/managing-databases/template-databases)。 資料庫的編碼儲存在系統目錄 pg\_database 中。您可以使用 psql -l 選項或 \l 指令查看。 ``` $ psql -l List of databases Name | Owner | Encoding | Collation | Ctype | Access Privileges -----------+----------+-----------+-------------+-------------+------------------------------------- clocaledb | hlinnaka | SQL_ASCII | C | C | englishdb | hlinnaka | UTF8 | en_GB.UTF8 | en_GB.UTF8 | japanese | hlinnaka | UTF8 | ja_JP.UTF8 | ja_JP.UTF8 | korean | hlinnaka | EUC_KR | ko_KR.euckr | ko_KR.euckr | postgres | hlinnaka | UTF8 | fi_FI.UTF8 | fi_FI.UTF8 | template0 | hlinnaka | UTF8 | fi_FI.UTF8 | fi_FI.UTF8 | {=c/hlinnaka,hlinnaka=CTc/hlinnaka} template1 | hlinnaka | UTF8 | fi_FI.UTF8 | fi_FI.UTF8 | {=c/hlinnaka,hlinnaka=CTc/hlinnaka} (7 rows) ``` **注意**\ 在大多數現代作業系統上，PostgreSQL 可以確定 LC\_CTYPE 設定所隱含的字元集，並強制只使用相符合的資料庫編碼。在較舊的系統上，您有責任確保使用所選區域設定所需的編碼。此區域中的錯誤可能會導致與區域設定相關操作（如排序）的奇怪行為。 即使 LC\_CTYPE 不是 C 或 POSIX，PostgreSQL 也允許超級使用者使用 SQL\_ASCII 編碼建立資料庫。如上所述，SQL\_ASCII 不強制儲存在資料庫中的資料具有任何特定編碼，因此這種選擇會帶來相依於語言環境的錯誤行為風險。不推薦使用這種設定組合，有一天可能會被禁止使用。 ## 24.3.3. 伺服器和用戶端之間的自動字元集轉換 PostgreSQL 支援伺服器和用戶端之間針對某些字元集組合的自動字元集轉換。轉換訊息儲存在 pg\_conversion 系統目錄中。PostgreSQL 帶有一些預先定義的轉換，如 [Table 23.2](#table-23-2-client-server-character-set-conversions) 所示。您可以使用 SQL 指令 CREATE CONVERSION 建立新的轉換。 #### **Table 23.2. Client/Server Character Set Conversions** | Server Character Set | Available Client Character Sets | | -------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------- | | `BIG5` | *not supported as a server encoding* | | `EUC_CN` | *EUC\_CN*, `MULE_INTERNAL`, `UTF8` | | `EUC_JP` | *EUC\_JP*, `MULE_INTERNAL`, `SJIS`, `UTF8` | | `EUC_KR` | *EUC\_KR*, `MULE_INTERNAL`, `UTF8` | | `EUC_TW` | *EUC\_TW*, `BIG5`, `MULE_INTERNAL`, `UTF8` | | `GB18030` | *not supported as a server encoding* | | `GBK` | *not supported as a server encoding* | | `ISO_8859_5` | *ISO\_8859\_5*, `KOI8R`, `MULE_INTERNAL`, `UTF8`, `WIN866`, `WIN1251` | | `ISO_8859_6` | *ISO\_8859\_6*, `UTF8` | | `ISO_8859_7` | *ISO\_8859\_7*, `UTF8` | | `ISO_8859_8` | *ISO\_8859\_8*, `UTF8` | | `JOHAB` | *JOHAB*, `UTF8` | | `KOI8R` | *KOI8R*, `ISO_8859_5`, `MULE_INTERNAL`, `UTF8`, `WIN866`, `WIN1251` | | `KOI8U` | *KOI8U*, `UTF8` | | `LATIN1` | *LATIN1*, `MULE_INTERNAL`, `UTF8` | | `LATIN2` | *LATIN2*, `MULE_INTERNAL`, `UTF8`, `WIN1250` | | `LATIN3` | *LATIN3*, `MULE_INTERNAL`, `UTF8` | | `LATIN4` | *LATIN4*, `MULE_INTERNAL`, `UTF8` | | `LATIN5` | *LATIN5*, `UTF8` | | `LATIN6` | *LATIN6*, `UTF8` | | `LATIN7` | *LATIN7*, `UTF8` | | `LATIN8` | *LATIN8*, `UTF8` | | `LATIN9` | *LATIN9*, `UTF8` | | `LATIN10` | *LATIN10*, `UTF8` | | `MULE_INTERNAL` | *MULE\_INTERNAL*, `BIG5`, `EUC_CN`, `EUC_JP`, `EUC_KR`, `EUC_TW`, `ISO_8859_5`, `KOI8R`, `LATIN1` to `LATIN4`, `SJIS`, `WIN866`, `WIN1250`, `WIN1251` | | `SJIS` | *not supported as a server encoding* | | `SQL_ASCII` | *any (no conversion will be performed)* | | `UHC` | *not supported as a server encoding* | | `UTF8` | *all supported encodings* | | `WIN866` | *WIN866*, `ISO_8859_5`, `KOI8R`, `MULE_INTERNAL`, `UTF8`, `WIN1251` | | `WIN874` | *WIN874*, `UTF8` | | `WIN1250` | *WIN1250*, `LATIN2`, `MULE_INTERNAL`, `UTF8` | | `WIN1251` | *WIN1251*, `ISO_8859_5`, `KOI8R`, `MULE_INTERNAL`, `UTF8`, `WIN866` | | `WIN1252` | *WIN1252*, `UTF8` | | `WIN1253` | *WIN1253*, `UTF8` | | `WIN1254` | *WIN1254*, `UTF8` | | `WIN1255` | *WIN1255*, `UTF8` | | `WIN1256` | *WIN1256*, `UTF8` | | `WIN1257` | *WIN1257*, `UTF8` | | `WIN1258` | *WIN1258*, `UTF8` | 要啟用自動字元集轉換，您必須告訴 PostgreSQL 您要在用戶端中使用的字元集（編碼）。有幾種方法可以實現此目的： * 在 psql 中使用 \encoding 指令。\encoding 允許您即時更改用戶端編碼。例如，要將編碼更改為 SJIS，請鍵入： ``` \encoding SJIS ``` * libpq（[第 33.10 節](https://docs.postgresql.tw/15/client-interfaces/libpq-c-library/control-functions)）具有控制用戶端編碼的功能。 * 使用 SET client\_encoding TO。可以使用以下 SQL 指令設定用戶端編碼： ``` SET CLIENT_ENCODING TO 'value'; ``` 您還可以使用標準 SQL 語法 SET NAMES 來達到此目的： ``` SET NAMES 'value'; ``` 要查詢目前用戶端編碼： ``` SHOW client_encoding; ``` 要回傳預設編碼： ``` RESET client_encoding; ``` * 使用 PGCLIENTENCODING。如果在用戶端環境中定義了環境變數 PGCLIENTENCODING，則在建立與伺服器的連線時會自動選擇該用戶端編碼。（這可以隨後使用上面提到的任何其他方法覆蓋。） * 使用組態變數 client\_encoding。如果設定了 [client\_encoding](https://docs.postgresql.tw/15/server-configuration/client-connection-defaults#client_encoding-string) 變數，則在建立與伺服器的連線時會自動選擇該用戶端編碼。（這可以隨後使用上面提到的任何其他方法覆蓋。） 如果無法轉換特定字元 - 假設您為伺服器選擇了 EUC\_JP 而為用戶端選擇了 LATIN1，並且回傳了一些在 LATIN1 中沒有表示的日文字元 - 回報錯誤。 如果用戶端字元集定義為 SQL\_ASCII，則無論伺服器的字元集如何，都將停用編碼轉換。就像伺服器一樣，除非使用全 ASCII 資料，否則使用 SQL\_ASCII 是不明智的。 ## 24.3.4. Available Character Set Conversions PostgreSQL allows conversion between any two character sets for which a conversion function is listed in the [`pg_conversion`](https://www.postgresql.org/docs/15/catalog-pg-conversion.html) system catalog. PostgreSQL comes with some predefined conversions, as summarized in [Table 24.2](https://www.postgresql.org/docs/15/multibyte.html#MULTIBYTE-TRANSLATION-TABLE) and shown in more detail in [Table 24.3](https://www.postgresql.org/docs/15/multibyte.html#BUILTIN-CONVERSIONS-TABLE). You can create a new conversion using the SQL command [CREATE CONVERSION](https://www.postgresql.org/docs/15/sql-createconversion.html). (To be used for automatic client/server conversions, a conversion must be marked as “default” for its character set pair.) **Table 24.2. Built-in Client/Server Character Set Conversions** | Server Character Set | Available Client Character Sets | | -------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------- | | `BIG5` | *not supported as a server encoding* | | `EUC_CN` | *EUC\_CN*, `MULE_INTERNAL`, `UTF8` | | `EUC_JP` | *EUC\_JP*, `MULE_INTERNAL`, `SJIS`, `UTF8` | | `EUC_JIS_2004` | *EUC\_JIS\_2004*, `SHIFT_JIS_2004`, `UTF8` | | `EUC_KR` | *EUC\_KR*, `MULE_INTERNAL`, `UTF8` | | `EUC_TW` | *EUC\_TW*, `BIG5`, `MULE_INTERNAL`, `UTF8` | | `GB18030` | *not supported as a server encoding* | | `GBK` | *not supported as a server encoding* | | `ISO_8859_5` | *ISO\_8859\_5*, `KOI8R`, `MULE_INTERNAL`, `UTF8`, `WIN866`, `WIN1251` | | `ISO_8859_6` | *ISO\_8859\_6*, `UTF8` | | `ISO_8859_7` | *ISO\_8859\_7*, `UTF8` | | `ISO_8859_8` | *ISO\_8859\_8*, `UTF8` | | `JOHAB` | *not supported as a server encoding* | | `KOI8R` | *KOI8R*, `ISO_8859_5`, `MULE_INTERNAL`, `UTF8`, `WIN866`, `WIN1251` | | `KOI8U` | *KOI8U*, `UTF8` | | `LATIN1` | *LATIN1*, `MULE_INTERNAL`, `UTF8` | | `LATIN2` | *LATIN2*, `MULE_INTERNAL`, `UTF8`, `WIN1250` | | `LATIN3` | *LATIN3*, `MULE_INTERNAL`, `UTF8` | | `LATIN4` | *LATIN4*, `MULE_INTERNAL`, `UTF8` | | `LATIN5` | *LATIN5*, `UTF8` | | `LATIN6` | *LATIN6*, `UTF8` | | `LATIN7` | *LATIN7*, `UTF8` | | `LATIN8` | *LATIN8*, `UTF8` | | `LATIN9` | *LATIN9*, `UTF8` | | `LATIN10` | *LATIN10*, `UTF8` | | `MULE_INTERNAL` | *MULE\_INTERNAL*, `BIG5`, `EUC_CN`, `EUC_JP`, `EUC_KR`, `EUC_TW`, `ISO_8859_5`, `KOI8R`, `LATIN1` to `LATIN4`, `SJIS`, `WIN866`, `WIN1250`, `WIN1251` | | `SJIS` | *not supported as a server encoding* | | `SHIFT_JIS_2004` | *not supported as a server encoding* | | `SQL_ASCII` | *any (no conversion will be performed)* | | `UHC` | *not supported as a server encoding* | | `UTF8` | *all supported encodings* | | `WIN866` | *WIN866*, `ISO_8859_5`, `KOI8R`, `MULE_INTERNAL`, `UTF8`, `WIN1251` | | `WIN874` | *WIN874*, `UTF8` | | `WIN1250` | *WIN1250*, `LATIN2`, `MULE_INTERNAL`, `UTF8` | | `WIN1251` | *WIN1251*, `ISO_8859_5`, `KOI8R`, `MULE_INTERNAL`, `UTF8`, `WIN866` | | `WIN1252` | *WIN1252*, `UTF8` | | `WIN1253` | *WIN1253*, `UTF8` | | `WIN1254` | *WIN1254*, `UTF8` | | `WIN1255` | *WIN1255*, `UTF8` | | `WIN1256` | *WIN1256*, `UTF8` | | `WIN1257` | *WIN1257*, `UTF8` | | `WIN1258` | *WIN1258*, `UTF8` | **Table 24.3. All Built-in Character Set Conversions** | Conversion Name [\[a\]](https://www.postgresql.org/docs/15/multibyte.html#ftn.id-1.6.11.5.8.4.2.4.1.1.1) | Source Encoding | Destination Encoding | | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------- | -------------------- | | `big5_to_euc_tw` | `BIG5` | `EUC_TW` | | `big5_to_mic` | `BIG5` | `MULE_INTERNAL` | | `big5_to_utf8` | `BIG5` | `UTF8` | | `euc_cn_to_mic` | `EUC_CN` | `MULE_INTERNAL` | | `euc_cn_to_utf8` | `EUC_CN` | `UTF8` | | `euc_jp_to_mic` | `EUC_JP` | `MULE_INTERNAL` | | `euc_jp_to_sjis` | `EUC_JP` | `SJIS` | | `euc_jp_to_utf8` | `EUC_JP` | `UTF8` | | `euc_kr_to_mic` | `EUC_KR` | `MULE_INTERNAL` | | `euc_kr_to_utf8` | `EUC_KR` | `UTF8` | | `euc_tw_to_big5` | `EUC_TW` | `BIG5` | | `euc_tw_to_mic` | `EUC_TW` | `MULE_INTERNAL` | | `euc_tw_to_utf8` | `EUC_TW` | `UTF8` | | `gb18030_to_utf8` | `GB18030` | `UTF8` | | `gbk_to_utf8` | `GBK` | `UTF8` | | `iso_8859_10_to_utf8` | `LATIN6` | `UTF8` | | `iso_8859_13_to_utf8` | `LATIN7` | `UTF8` | | `iso_8859_14_to_utf8` | `LATIN8` | `UTF8` | | `iso_8859_15_to_utf8` | `LATIN9` | `UTF8` | | `iso_8859_16_to_utf8` | `LATIN10` | `UTF8` | | `iso_8859_1_to_mic` | `LATIN1` | `MULE_INTERNAL` | | `iso_8859_1_to_utf8` | `LATIN1` | `UTF8` | | `iso_8859_2_to_mic` | `LATIN2` | `MULE_INTERNAL` | | `iso_8859_2_to_utf8` | `LATIN2` | `UTF8` | | `iso_8859_2_to_windows_1250` | `LATIN2` | `WIN1250` | | `iso_8859_3_to_mic` | `LATIN3` | `MULE_INTERNAL` | | `iso_8859_3_to_utf8` | `LATIN3` | `UTF8` | | `iso_8859_4_to_mic` | `LATIN4` | `MULE_INTERNAL` | | `iso_8859_4_to_utf8` | `LATIN4` | `UTF8` | | `iso_8859_5_to_koi8_r` | `ISO_8859_5` | `KOI8R` | | `iso_8859_5_to_mic` | `ISO_8859_5` | `MULE_INTERNAL` | | `iso_8859_5_to_utf8` | `ISO_8859_5` | `UTF8` | | `iso_8859_5_to_windows_1251` | `ISO_8859_5` | `WIN1251` | | `iso_8859_5_to_windows_866` | `ISO_8859_5` | `WIN866` | | `iso_8859_6_to_utf8` | `ISO_8859_6` | `UTF8` | | `iso_8859_7_to_utf8` | `ISO_8859_7` | `UTF8` | | `iso_8859_8_to_utf8` | `ISO_8859_8` | `UTF8` | | `iso_8859_9_to_utf8` | `LATIN5` | `UTF8` | | `johab_to_utf8` | `JOHAB` | `UTF8` | | `koi8_r_to_iso_8859_5` | `KOI8R` | `ISO_8859_5` | | `koi8_r_to_mic` | `KOI8R` | `MULE_INTERNAL` | | `koi8_r_to_utf8` | `KOI8R` | `UTF8` | | `koi8_r_to_windows_1251` | `KOI8R` | `WIN1251` | | `koi8_r_to_windows_866` | `KOI8R` | `WIN866` | | `koi8_u_to_utf8` | `KOI8U` | `UTF8` | | `mic_to_big5` | `MULE_INTERNAL` | `BIG5` | | `mic_to_euc_cn` | `MULE_INTERNAL` | `EUC_CN` | | `mic_to_euc_jp` | `MULE_INTERNAL` | `EUC_JP` | | `mic_to_euc_kr` | `MULE_INTERNAL` | `EUC_KR` | | `mic_to_euc_tw` | `MULE_INTERNAL` | `EUC_TW` | | `mic_to_iso_8859_1` | `MULE_INTERNAL` | `LATIN1` | | `mic_to_iso_8859_2` | `MULE_INTERNAL` | `LATIN2` | | `mic_to_iso_8859_3` | `MULE_INTERNAL` | `LATIN3` | | `mic_to_iso_8859_4` | `MULE_INTERNAL` | `LATIN4` | | `mic_to_iso_8859_5` | `MULE_INTERNAL` | `ISO_8859_5` | | `mic_to_koi8_r` | `MULE_INTERNAL` | `KOI8R` | | `mic_to_sjis` | `MULE_INTERNAL` | `SJIS` | | `mic_to_windows_1250` | `MULE_INTERNAL` | `WIN1250` | | `mic_to_windows_1251` | `MULE_INTERNAL` | `WIN1251` | | `mic_to_windows_866` | `MULE_INTERNAL` | `WIN866` | | `sjis_to_euc_jp` | `SJIS` | `EUC_JP` | | `sjis_to_mic` | `SJIS` | `MULE_INTERNAL` | | `sjis_to_utf8` | `SJIS` | `UTF8` | | `windows_1258_to_utf8` | `WIN1258` | `UTF8` | | `uhc_to_utf8` | `UHC` | `UTF8` | | `utf8_to_big5` | `UTF8` | `BIG5` | | `utf8_to_euc_cn` | `UTF8` | `EUC_CN` | | `utf8_to_euc_jp` | `UTF8` | `EUC_JP` | | `utf8_to_euc_kr` | `UTF8` | `EUC_KR` | | `utf8_to_euc_tw` | `UTF8` | `EUC_TW` | | `utf8_to_gb18030` | `UTF8` | `GB18030` | | `utf8_to_gbk` | `UTF8` | `GBK` | | `utf8_to_iso_8859_1` | `UTF8` | `LATIN1` | | `utf8_to_iso_8859_10` | `UTF8` | `LATIN6` | | `utf8_to_iso_8859_13` | `UTF8` | `LATIN7` | | `utf8_to_iso_8859_14` | `UTF8` | `LATIN8` | | `utf8_to_iso_8859_15` | `UTF8` | `LATIN9` | | `utf8_to_iso_8859_16` | `UTF8` | `LATIN10` | | `utf8_to_iso_8859_2` | `UTF8` | `LATIN2` | | `utf8_to_iso_8859_3` | `UTF8` | `LATIN3` | | `utf8_to_iso_8859_4` | `UTF8` | `LATIN4` | | `utf8_to_iso_8859_5` | `UTF8` | `ISO_8859_5` | | `utf8_to_iso_8859_6` | `UTF8` | `ISO_8859_6` | | `utf8_to_iso_8859_7` | `UTF8` | `ISO_8859_7` | | `utf8_to_iso_8859_8` | `UTF8` | `ISO_8859_8` | | `utf8_to_iso_8859_9` | `UTF8` | `LATIN5` | | `utf8_to_johab` | `UTF8` | `JOHAB` | | `utf8_to_koi8_r` | `UTF8` | `KOI8R` | | `utf8_to_koi8_u` | `UTF8` | `KOI8U` | | `utf8_to_sjis` | `UTF8` | `SJIS` | | `utf8_to_windows_1258` | `UTF8` | `WIN1258` | | `utf8_to_uhc` | `UTF8` | `UHC` | | `utf8_to_windows_1250` | `UTF8` | `WIN1250` | | `utf8_to_windows_1251` | `UTF8` | `WIN1251` | | `utf8_to_windows_1252` | `UTF8` | `WIN1252` | | `utf8_to_windows_1253` | `UTF8` | `WIN1253` | | `utf8_to_windows_1254` | `UTF8` | `WIN1254` | | `utf8_to_windows_1255` | `UTF8` | `WIN1255` | | `utf8_to_windows_1256` | `UTF8` | `WIN1256` | | `utf8_to_windows_1257` | `UTF8` | `WIN1257` | | `utf8_to_windows_866` | `UTF8` | `WIN866` | | `utf8_to_windows_874` | `UTF8` | `WIN874` | | `windows_1250_to_iso_8859_2` | `WIN1250` | `LATIN2` | | `windows_1250_to_mic` | `WIN1250` | `MULE_INTERNAL` | | `windows_1250_to_utf8` | `WIN1250` | `UTF8` | | `windows_1251_to_iso_8859_5` | `WIN1251` | `ISO_8859_5` | | `windows_1251_to_koi8_r` | `WIN1251` | `KOI8R` | | `windows_1251_to_mic` | `WIN1251` | `MULE_INTERNAL` | | `windows_1251_to_utf8` | `WIN1251` | `UTF8` | | `windows_1251_to_windows_866` | `WIN1251` | `WIN866` | | `windows_1252_to_utf8` | `WIN1252` | `UTF8` | | `windows_1256_to_utf8` | `WIN1256` | `UTF8` | | `windows_866_to_iso_8859_5` | `WIN866` | `ISO_8859_5` | | `windows_866_to_koi8_r` | `WIN866` | `KOI8R` | | `windows_866_to_mic` | `WIN866` | `MULE_INTERNAL` | | `windows_866_to_utf8` | `WIN866` | `UTF8` | | `windows_866_to_windows_1251` | `WIN866` | `WIN` | | `windows_874_to_utf8` | `WIN874` | `UTF8` | | `euc_jis_2004_to_utf8` | `EUC_JIS_2004` | `UTF8` | | `utf8_to_euc_jis_2004` | `UTF8` | `EUC_JIS_2004` | | `shift_jis_2004_to_utf8` | `SHIFT_JIS_2004` | `UTF8` | | `utf8_to_shift_jis_2004` | `UTF8` | `SHIFT_JIS_2004` | | `euc_jis_2004_to_shift_jis_2004` | `EUC_JIS_2004` | `SHIFT_JIS_2004` | | `shift_jis_2004_to_euc_jis_2004` | `SHIFT_JIS_2004` | `EUC_JIS_2004` | | [\[a\]](https://www.postgresql.org/docs/15/multibyte.html#id-1.6.11.5.8.4.2.4.1.1.1) The conversion names follow a standard naming scheme: The official name of the source encoding with all non-alphanumeric characters replaced by underscores, followed by `_to_`, followed by the similarly processed destination encoding name. Therefore, these names sometimes deviate from the customary encoding names shown in [Table 24.1](https://www.postgresql.org/docs/15/multibyte.html#CHARSET-TABLE). | | | ## 24.3.5. 延伸閱讀 這些是開始學習各種編碼系統的好資源。 * CJKV 訊息處理：中文，日文，韓文和越南文運算 * 包含 EUC\_JP，EUC\_CN，EUC\_KR，EUC\_TW 的詳細說明。 * [http://www.unicode.org/](http://www.unicode.org) * Unicode Consortium 的網站。 * RFC 3629 * UTF-8 (8-bit UCS/Unicode Transformation Format) 定義在這裡