ticoAg/ChineseCorpus-Kaggle-fanti huggingface dataset:
中間市、直方市、飯塚市、宮若市、嘉麻市、蘆屋町、水卷町、岡垣町、遠賀町、小竹町、鞍手町、桂川町
神奈川縣第11區是日本眾議院的一個小選區，設於1994年。範圍包括橫須賀市、三浦市。2016年的選民人數為390,168人。
胡賢才，河南省新縣人。中國人民解放軍將領。
1930年4月參加中國工農紅軍，1935年11月加入中國共產黨。第一次國共內戰時期，曾任中共河南省羅山特委便衣隊長，參加了鄂豫皖邊區三年游擊戰。抗日戰爭初期，在新四軍第四支隊任排長、連長。1941年以后，任新四軍第二師兼淮南軍區獨立旅四團一營營氏，新四軍淮南軍區獨立團副團長，新四軍第二師六旅十七團團長。第二次國共內戰期間，任華東野戰軍第六縱隊十八師五十二團團長，第三縱隊九師副參謀長，第三野戰軍二十二軍六十四師參謀長、副師長兼參謀長。
中華人民共和國成立以后，歷任浙江軍區第十軍分區副司令員，二十二軍六十六師師長，六十八軍副軍長，濟南軍區副參謀長，濟南軍區司令部顧問。1964年，晉升為少將軍銜。1983年4月，在北京逝世。
哈克橋（Hackerbrücke）是一座位于德國慕尼黑火車總站西側的天橋，建于19世紀70年代。哈克橋北側有慕尼黑汽車總站，橋下有同名快軌站——哈克橋站。
*J. H. Biller and H.-P. Rasp, ''München, Kunst & Kultur'', Munich: Südwest, ed. 18, 2006, p.&nbsp;155.
廣島縣第1區是日本眾議院的一個小選區，設於1994年。範圍包括廣島市中區、東區、南區。2016年的選民人數為327,065人。
2011年時的慕尼黑汽車總站
慕尼黑長途汽車總站（，一般使用其簡稱ZOB München）顧名思義是慕尼黑最大地理位置最為中心的長途汽車站，位于馬克斯近郊。該汽車站占地，于2009年9月11日建成，是慕尼黑最大的國際/國內汽車站。弗利克斯巴士、歐洲之線巴士和你的巴士線路均停靠此站，并在此設有客戶服務中心。該車站附近有快軌站黑客橋站。
哈克橋站是一座慕尼黑快鐵1-4，6-8號線位于馬克斯近郊的一座車站，毗鄰哈克橋。此站可抵達慕尼黑最大的汽車站——慕尼黑汽車總站。
神奈川縣第2區是日本眾議院的一個小選區，設於1994年。範圍包括橫濱市西區、南區、港南區。2016年的選民人數為431,794人。
SQL編程語言的語法是由ISO/IEC 9075標準中的ISO/IEC SC 32委員會所定義和維護的。盡管存在標準，不過SQL代碼仍然無法在不進行修改的前提下在不同的數據庫系統中直接移植。
* 表達式，可以產生任何標量值，或由和的數據庫表
不等于（許多-{zh-cn:數據庫;zh-tw:資料庫}-管理系統除了支持以外還支持）
在一個范圍內
字符模式匹配
等于多個可能的值之一
與空值（數據缺失）比較
等于值或均為空值（數據缺失）
用于在查看結果時更改字段名稱
有人也提議實現其他運算子，例如（尋找那些不比任何其他記錄“糟糕”的記錄）。
SQL在SQL-92標準中引入了CASE/WHEN/THEN/ELSE/END語句。通常情況下所稱的“搜索CASE語句”例子如下：
CASE WHEN n > 0
THEN '正'
WHEN n
SQL按照WHEN條件在源代碼中出現的順序進行判斷。如果源代碼中沒有指定ELSE表達式，SQL默認為ELSE NULL。SQL標準中還有一種“簡單CASE語句”，類似C語言的switch：
CASE n WHEN 1
THEN 'one'
WHEN 2
THEN 'two'
ELSE 'I cannot count that high'
該語法是隱式相等條件。通常情況下，遇到與空值比較的情況會發出警告。
對于Oracle數據庫的SQL語法，還可以用DECODE函數簡化：
SELECT DECODE(n, 1, 'one',
2, 'two',
'i cannot count that high')
FROM   some_table;
最后一個值是可選的，若無指定，默認為NULL。另外，與“簡單CASE”不同的是，Oracle的DECODE會認為兩個NULL之間相等。
SQL中最常見的操作是查詢，它是通過陳述性SELECT語句執行的。SELECT從一個或多個表或表達式中檢索數據。標準的SELECT不會對數據庫有持久影響。SELECT的一些非標準的實現可以有持久影響，如一些數據庫中有SELECT INTO語法。
查詢允許用戶描述所需的數據，將、以及執行用以產生它選取的結果的物理操作交給數據庫管理系統（DBMS）負責。
查詢包含一系列含有最終結果的字段, 緊跟SELECT關鍵詞。星號（"*"）也可以用來指定查詢應當返回查詢表所有字段。SELECT是最復雜的SQL語句，可選的關鍵詞和子句包括：
* FROM子句指定了選擇的數據表。FROM子句也可以包含JOIN 二層子句來為數據表的連接設置規則。
* WHERE子句后接一個比較謂詞以限制返回的行。WHERE子句僅保留返回結果里使得比較謂詞的值為True的行。
* GROUP BY子句用于將若干含有相同值的行合并。 GROUP BY通常與SQL聚合函數連用，或者用于清除數據重復的行。GROUP BY子句要用在WHERE子句之后。
* HAVING子句后接一個謂詞來過濾從GROUP BY子句中獲得的結果，由于其作用于GROUP BY子句之上，所以聚合函數也可以放到其謂詞中。
* ORDER BY子句指明將哪個字段用作排序關鍵字，以及排序順序(升序/降序)，如果無此子句，那么返回結果的順序不能保證有序。
下面是一個返回昂貴的書籍列表的SELECT查詢的例子。查詢會從 ''Book'' 表中檢索所有 ''price'' 的值大于 100.00 的行。結果按 ''title'' 升序排列。''選擇列表''中的星號（*）表明''Book''表中所有字段都包含在結果集中。
FROM  Book
WHERE price > 100.00
ORDER BY title;
下面的例子演示了通過返回與每本書相關聯的書籍和作者來多表查詢、分組和聚集。
SELECT Book.title AS Title,
count(*) AS Authors
JOIN  Book_author
ON  Book.isbn = Book_author.isbn
GROUP BY Book.title;
輸出可能類似于下面的例子：
Title                  Authors
---------------------- -------
SQL Examples and Guide 4
The Joy of SQL         1
An Introduction to SQL 2
Pitfalls of SQL        1
在''isbn''是兩個表中唯一通用的列名，且名為''title''的列僅存在于''Books''表中的前提下，上述查詢可以用以下形式重寫：
SELECT title,
NATURAL JOIN Book_author
GROUP BY title;
然而，許多廠商或者不支持這種方法，或者需要某些列命名約定來實現自然聯接。
SQL包含有用于計算存儲值的值的運算符和函數。SQL允許在''選擇列表''中使用表達式來投影數據，如下例所示，它返回成本超過100.00的書籍列表，另外一列''sales_tax''包含以''price''的6％計算的銷售稅數據。
SELECT isbn,
title,
price,
price * 0.06 AS sales_tax
查詢可以嵌套，以便一個查詢的結果可以通過關系運算符或聚合函數在另一個查詢中使用。嵌套查詢也稱為''子查詢''。雖然連接和其他表操作在許多情況下提供了計算上優越（即更快）的替代方案，但是子查詢的使用引入了在執行中會很有用或很必要的等級。在下例中，聚合函數AVG接收子查詢的結果作為輸入：
WHERE price
子查詢可以使用外部查詢的值，在這種情況下，它被稱為。
自1999年以來，SQL標準允許稱為的命名子查詢（在IBM DB2版本2中實現之后命名和設計; Oracle把它叫做）。CTE還可以通過自身引用來遞歸；允許樹或圖遍歷，以及更一般的不動點計算。
''派生表''是在FROM子句中引用SQL子查詢的用法。基本上，派生表是可以從中選擇或連接到的子查詢。派生表功能允許用戶將子查詢引用為表。派生表也稱為''內聯視圖''或''子選擇''。
在下例中，SQL語句涉及從初始“Book”表到派生表“sales”的連接。此派生表使用ISBN捕獲關聯的圖書銷售信息以加入“Book”表。因此，派生表提供的結果集包含附加列（銷售的商品數量和銷售圖書的公司）：
SELECT b.isbn, b.title, b.price, sales.items_sold, sales.company_nm
FROM Book b
JOIN (SELECT SUM(Items_Sold) Items_Sold, Company_Nm, ISBN
FROM Book_Sales
GROUP BY Company_Nm, ISBN) sales
ON sales.isbn = b.isbn
SQL中引入了空值的概念，用來處理關系模型中缺少信息的情況。NULL一詞表示空白值，是SQL中的保留詞。如果Null進行比較，例如在WHERE子句中使用“=”判斷相等，那么會返回未知值，而SELECT語句只會返回WHERE子句條件為真（TRUE）的結果，不會返回條件為假（FALSE）或未知的結果。
“真”、“假”以及與空值直接比較時所得到的“未知”共同組成了SQL的three-valued logic。SQL所用的真值表與Kleene和Lukasiewicz三值邏輯的共同部分對應 (它們對內涵的定義不同，然而SQL沒有定義這樣的操作)。
p AND q
p OR q
然而，由于在直接比較之外的處理，在SQL中對Null的語義解釋存在爭議。如上表所示，SQL中的兩個NULL之間的直接等式比較（例如NULL = NULL）返回真值“未知”。這符合Null不具有值（并不是任何數據域的成員）的解釋，而是缺失信息的占位符或“標記”。但是，在UNION和INTERSECT操作符的SQL規范中，兩個空值不相等的原則在實際上標識了null。 因此，與涉及NULL的顯式比較（例如上述WHERE子句中的那些）的操作不同，SQL中的這些集合運算可能產生表示不確定信息的結果。在Codd的1979年提案中（該提案基本被SQL92采納），這種語義上的不一致被合理化了，他認為在集合操作中刪除重復的操作發生在 "比檢索操作求值中的相等驗證更低的細節層次上"。 然而，計算機科學教授Ron van der Meyden認為“SQL標準的不一致意味著不可能將任何直觀的邏輯語義歸結為SQL中的null處理。”
另外，由于直接與空值比較會返回未知，因此SQL又提供了兩個用于測試空值的語句：IS NULL和IS NOT NULL，前者用于判斷是否為空，后者相反。 SQL不明確支持全稱量化，必須將其定義為否定存在量化。 還有“ IS DISTINCT FROM ”插入比較運算符，除非兩個操作數相等或兩者都為NULL，否則返回TRUE。同樣，IS NOT DISTINCT FROM定義為“NOT ( IS DISTINCT FROM )”。SQL:1999還引入了BOOLEAN類型變量，根據標準也可以是未知值。實踐中一些數據庫系統（例如PostgreSQL）會把 implement the BOOLEAN Unknown as a BOOLEAN NULL.
資料操縱語言（DML）是SQL用于添加、更新和刪除數據的子集：
* INSERT添加行（正式名稱為元組）到一個現有的表，例如：
INSERT INTO example
(field1, field2, field3)
('test', 'N', NULL);
* UPDATE修改現有的表中一些行，例如：
UPDATE example
SET field1 = 'updated value'
WHERE field2 = 'N';
* DELETE從表中刪除現有的行，如：
DELETE FROM example
* MERGE用來合并多個表的數據。它結合了INSERT和UPDATE元素。它是在SQL:2003標準中定義的；在那之前，一些數據庫也以不同的語法提供了相似的功能，又是叫做“”。
MERGE INTO table_name USING table_reference ON (condition)
WHEN MATCHED THEN
UPDATE SET column1 = value1 , column2 = value2 ...
WHEN NOT MATCHED THEN
INSERT (column1 , column2 ...) VALUES (value1 , value2 ...)
如果數據庫系統支持事務，那么可用以下語句：
* START TRANSACTION（或BEGIN WORK、BEGIN TRANSACTION，取決于具體數據庫系統的規定）表示數據庫事務開始。
* SAVE TRANSACTION（或SAVEPOINT）命令會記錄事務本身的狀態，即保存點。
CREATE TABLE tbl_1(id int);
INSERT INTO tbl_1(id) VALUES(1);
INSERT INTO tbl_1(id) VALUES(2);
UPDATE tbl_1 SET id=200 WHERE id=1;
SAVEPOINT id_1upd;
UPDATE tbl_1 SET id=1000 WHERE id=2;
ROLLBACK to id_1upd;
SELECT id from tbl_1;
* COMMIT會令事務過程中進行數據修改正式生效。
* ROLLBACK會放棄上次COMMIT或ROLLBACK之后的修改，使數據恢復到前一狀態。不過一旦COMMIT語句結束，事務所產生的修改將無法回退。
COMMIT和ROLLBACK會中止當前事務并釋放鎖。在沒有START TRANSACTION或類似語句的情況下，SQL的語義與實現有關的。
下面例子展示了把一個賬戶的金額轉移到另一個賬戶上面的過程。只要表示減少和增加的兩個UPDATE語句中有一個失敗，整個事務就會回退，更改也不會保存到數據庫中。
START TRANSACTION;
UPDATE Account SET amount=amount-200 WHERE account_number=1234;
UPDATE Account SET amount=amount+200 WHERE account_number=2345;
IF ERRORS=0 COMMIT;
IF ERRORS0 ROLLBACK;
資料定義語言（DDL）管理表和索引結構。DDL的最基本是CREATE、ALTER、RENAME、DROP和TRUNCATE語句：
* CREATE在數據庫中創建一個對象（例如一張表），舉例來說：
CREATE TABLE example(
column1 INTEGER,
column2 VARCHAR(50),
column3 DATE NOT NULL,
PRIMARY KEY (column1, column2)
* ALTER以不同方式修改現有對象的結構，例如向現有的表或約束添加字段：
ALTER TABLE example ADD column4 NUMBER(3) NOT NULL;
* TRUNCATE以一種非常快速的方式刪除表中的所有數據，刪除表內的數據而不是表本身。這通常意味著后續的COMMIT操作, 即，它不能被回滾（與DELETE不同，數據不會為之后回滾而寫入日志）。
TRUNCATE TABLE example;
* DROP刪除數據庫中的對象，通常無法挽回的，即，它不能被回滾，如：
DROP TABLE example;
一張表中的每個字段都要定義該字段的類型。ANSI SQL包括下列數據類型：
* CHARACTER(n)或CHAR(n)：寬度為n的定長字符串。如果內容長度不足，則以空格填充；
* CHARACTER VARYING(n)或VARCHAR(n)：最長為n個字符的可變寬度字符串；
* NATIONAL CHARACTER(n)或NCHAR(n)：支持國際字符集的固定寬度字符串；
* NATIONAL CHARACTER VARYING(n)或NVARCHAR(n)：可變寬度的NCHAR字符串；
Bit是一種存儲0或1的整數類型，一個Bit值需要一個字節。
* BIT(n)：n比特Bit類型
* BIT VARYING(n)：最大長度為n的Bit類型
* 整數：包括SMALLINT、INTEGER和BIGINT，可表示的數據范圍從小到大。
* 小數：包括FLOAT, REAL和DOUBLE PRECISION，可表示的數據范圍從小到大。
* 定點數：包括NUMERIC(長度, 精度) or DECIMAL(長度, 精度)。
定點數類型包含兩個要素：長度、精度。長度表示數字的最大個數，包括小數點左面和右面的數字。精度是非負整數，精度為零意味著數值只能是整數。以123.45為例，它的長度為5，精度為2。
SQL提供了除去小數部分、只保留整數部分的函數，叫做TRUNC（Informix、DB2、PostgreSQL、Oracle和MySQL）或ROUND（Informix、SQLite、Sybase、Oracle、PostgreSQL和Microsoft SQL Server）
* DATE：日期值（例如 2011-05-03）
* TIME：時間值（例如 15:51:36）。時間值的粒度通常是100納秒。
* TIME WITH TIME ZONE或TIMETZ：與TIME相同，但包含時區信息。
* TIMESTAMP：時間戳，同時包含日期和時間（例如 2011-05-03 15:51:36）。
* TIMESTAMP WITH TIME ZONE或TIMESTAMPTZ：與TIMESTAMP相同，但包含時區信息。
SQL提供了多個在日期時間類型和字符串類型之間互相轉換的函數，例如TO_DATE、TO_TIME、TO_TIMESTAMP等。可以通過NOW函數來獲取數據庫服務器的時間。
資料控制語言 (Data Control Language, DCL) 授權的用戶訪問和操作的數據。
它的兩個主要的語句是：
* GRANT 授權的一個或多個用戶執行在一個對象上的一個操作或者一組操作。
* REVOKE 消除了授權，其可以是默認的授權。
GRANT SELECT, UPDATE
ON example
TO some_user, another_user;
REVOKE SELECT, UPDATE
FROM some_user, another_user;
慕尼黑機場站是一座慕尼黑快鐵1號線和8號線位于慕尼黑機場的一座車站，從此站下車可抵達慕尼黑機場1號航站樓和2號航站樓。兩條線路車次一般為20分鐘，高峰時段輪番發車，平均車次為10分鐘。
陳凱柏（Chan Hoi Pak Paco，1999年1月29日－），生於香港，香港足球運動員，司職左中場，現時就讀香港浸會大學副學士和效力香港超級聯賽球會冠忠南區。
陳凱柏生於香港，其舅父黃覺恩年輕時曾效力甲組球會南華和星島，於8歲時就加入傳統球會南華的青訓精英班，並與教練兼前南華名宿陳志康結緣，到第二季由於灣仔與南華合作，所以陳凱柏便追隨教練陳志康加入新組成灣仔南華U11青年軍，到2012年太陽國際體育會成立，而陳凱柏便順理成章再隨總監陳志康轉會，成為太陽國際第一代青訓成員。
到2017年8月，他在跟隨港超聯球會冠忠南區操練，兼得到太陽國際體育會總監陳志康及青訓發展經理丘建威大力引薦，於8月30日加盟南區，而隨後隨住菁英盃改制，規定每隊每場必須派出最少兩名U22球員上陣，使陳凱柏於2017年10月28日對標準流浪的菁英盃分組賽，迎來職業球員生涯的處子戰，而他更正選登場，直到79分鐘由-{于}-楊後備入替，惟最終南區以1–2落敗。
19/20與20/21球季，陳凱柏不單在菁英盃獲得冠忠南區重用，聯賽也獲得一些上陣機會。
鄭子森（Cheng Tsz Sum，），生於香港，香港足球運動員，司職左中場，現時效力香港超級聯賽球隊標準流浪
鄭子森生於香港，於13歲開始接觸足球，並與朋友一起加入葵青區隊，代表流浪在五人聯賽和預備組聯賽表現突出，曾為學校奪得葵青區D1學界冠軍，更在球會港超聯一隊已跟操一段時間，到2017年1月27日與理文流浪簽下職業合約，成為球會陣中港超成員，惟沒有上陣機會，到季尾隨流浪行政總裁馮嘉奇轉投新成立的港超聯球會理文，並在2017年10月28日對夢想FC的菁英盃分組賽正選登場，迎來職業球員生涯的處子戰，惟在踢足全場下，最終理文以1–2落敗。
2020年7月，港超聯球會東方足球隊宣布簽入鄭子森。身為菁英盃適齡球員的他，於2021年4月7日的決賽中正選上陣，並成功協助球隊奪得菁英盃冠軍。
鄭子森並非如大部分香港青年軍隊友一樣自小已是代表隊常客，只曾入選香港U20五人足球代表隊，直到17歲才首度代表香港青年軍。
於2016年更以隊長身份帶領香港學界代表隊在廣東珠海舉行的第13屆全國學生運動會男足預賽，以4戰全勝佳績脫穎而出歷史性殺入8強，躋身決賽周，於2017年5月獲徵召到U17港足備戰亞青盃外圍賽，更在8月19日與曼聯U16青年軍進行賽馬會青少年足球精英匯的友賽中，用非慣用腳的右腳取得首個代表隊入球，追平2–2，結果香港以2–3僅負曼聯U16。
京都府第2區是日本眾議院的一個小選區，設於1994年。範圍包括京都市左京區、東山區、山科區。2016年的選民人數為270,744人。
埼玉縣第5區是日本眾議院的一個小選區，設於1994年。範圍包括埼玉市西區、北區、大宮區、中央區以及見沼區的一部分。2016年的選民人數為371,683人。
大宮市、與野市
埼玉市大宮區、西區、北區、中央區
埼玉市大宮區、西區、北區、中央區、見沼區
李貴可以指：
* 李貴 (宣德丁未進士)，宣德二年進士、明朝政治人物
* 李貴 (宣德庚戌進士)，宣德五年進士、明朝政治人物
* 李貴 (嘉靖進士)，嘉靖三十二年進士、明朝政治人物
* 李貴 (朝鮮)，朝鮮王朝中期大臣，曾參加仁祖反正
* 李貴 (1915年)，中共中央統戰部常務副部長、中華人民共和國政治人物
* 李貴 (武警)，武警水電指揮部副主任
* 李貴，紅樓夢人物、李嬤嬤子，賈寶玉之奶兄、貼身跟班
“獵迷”反潛巡邏機（英文：Hawker Siddeley Nimrod）是英國的海上巡邏機。該機由全世界第一種噴氣式客機哈維蘭彗星型（雖然這種客機並不成功）改裝而來。該機最初由德·哈維蘭公司及其破產后的繼承者研發。後期的研發則是由的后續公司英國航宇公司、英國宇航系統接受。
飛機是為英國皇家空軍替換過時的。“獵迷”MR1 / MR2 主要用途是固定翼反潛作戰飛機。次要用途是反艦作戰。從1970年代早期到2010年3月在役。 最后的型號研制MRA4由于嚴重預算透支、尚有700多飛安問題無錢徹底解決，最終于2010年強行銷毀所有試驗樣機。
1970年代，英國皇家空軍還以“獵迷”為基礎研制了海上偵察機、電子情報偵察機、空中預警機。但也是由于大量飛安問題無經費解決，全部于1986下馬，並改為引進7架E-3空中預警機取代。
Nimrod MR1 XV262 landing at RAF St Mawgan in July 1981
On 4 June 1964, the British Government issued Air Staff Requirement 381, which sought a replacement for the aging Avro Shackleton maritime patrol aircraft of the Royal Air Force (RAF). Such a replacement had been necessitated by the rapidly-approaching fatigue life limitations accumulated across the Shackleton fleet. A great deal of interest in the requirement was received from both British and foreign manufacturers, offered aircraft including the Lockheed P-3 Orion, the Breguet Atlantic and derivatives of the Hawker Siddeley Trident, BAC One-Eleven, Vickers VC10 and de Havilland Comet. On 2 February 1965, British Prime Minister Harold Wilson announced the intention to order Hawker Siddeley's maritime patrol version of the Comet, the HS.801.
The Nimrod design was based on that of the Comet 4 civil airliner which had reached the end of its commercial life (the first two prototype Nimrods, XV148 & XV147 were built from two final unfinished Comet 4C airframes). The Comet's turbojet engines were replaced by Rolls-Royce Spey turbofans for better fuel efficiency, particularly at the low altitudes required for maritime patrol. Major fuselage changes were made, including an internal weapons bay, an extended nose for radar, a new tail with electronic warfare (ESM) sensors mounted in a bulky fairing, and a MAD (magnetic anomaly detector) boom. After the first flight in May 1967, the RAF ordered a total of 46 Nimrod MR1s. The first example (XV230) entered service in October 1969. A total of five squadrons using the type were established; four were permanently based in the UK and a fifth was initially based in Malta.
Nimrod R1 XW665 landing during Waddington Airshow 2009
Three Nimrod aircraft were adapted for the signals intelligence role, replacing the Comet C2s and Canberras of No. 51 Squadron in May 1974. The R1 was visually distinguished from the MR2 by the lack of a MAD boom. It was fitted with an array of rotating dish aerials in the aircraft's bomb bay, with further dish aerials in the tailcone and at the front of the wing-mounted fuel tanks. It had a flight crew of four (two pilots, a flight engineer and one navigator) and up to 25 crew operating the SIGINT equipment.
Only since the end of the Cold War has the role of the aircraft been officially acknowledged; they were once described as "radar calibration aircraft". The R1s have not suffered the same rate of fatigue and corrosion as the MR2s. One R1 was lost in a flying accident since the type's introduction; this occurred in May 1995 during a flight test after major servicing, at RAF Kinloss. To replace this aircraft an MR2 was selected for conversion to R1 standard, and entered service in December 1996.
The Nimrod R1 was based initially at RAF Wyton, Cambridgeshire, and later at RAF Waddington in Lincolnshire, England, and flown by 51 Sqn. The two remaining Nimrod R1s were originally planned to be retired at the end of March 2011, but operational requirements forced the RAF to deploy one to RAF Akrotiri, Cyprus on 16 March in support of Operation Ellamy. The last flight of the type was on 28 June 2011 from RAF Waddington, in the presence of the Chief of the Air Staff, ACM Sir Stephen Dalton. XV 249, the former MR2, is now on display at the RAF Museum Cosford, West Midlands. The R1 was replaced by three Boeing RC-135W ''Rivet Joint'' aircraft, acquired under the Airseeker project; the first aircraft was delivered in late 2013.
Nimrod MR2 XV254 at a steep bank while displaying at the Royal International Air Tattoo, 2006
Starting in 1975, 35 aircraft were upgraded to MR2 standard, being re-delivered from August 1979. The upgrade included extensive modernisation of the aircraft's electronic suite. Changes included the replacement of the obsolete ASV Mk 21 radar used by the Shackleton and Nimrod MR1 with the new EMI Searchwater radar, a new acoustic processor (GEC-Marconi AQS-901) capable of handling more modern sonobouys, a new mission data recorder (Hanbush) and a new Electronic Support Measures (Yellow Gate) which included new pods on the wingtips.
Provision for in-flight refuelling was introduced during the Falklands War (as the ''MR2P''), as well as hardpoints to allow the Nimrod to carry the AIM-9 Sidewinder missile to counter enemy Argentine Air Force maritime surveillance aircraft. In preparation for operations in the Gulf War theatre, several MR2s were fitted with new communications and ECM equipment to deal with anticipated threats; at the time these modified aircraft were given the designation ''MR2P(GM) (Gulf Mod)''.
The Nimrod MR2 carried out three main roles – Anti-Submarine Warfare (ASW), Anti-Surface Unit Warfare (ASUW) and Search and Rescue (SAR). Its extended range enabled the crew to monitor maritime areas far to the north of Iceland and up to 4,000&nbsp;km out into the Western Atlantic. With Air-to-Air Refuelling (AAR), range and endurance was greatly extended. The crew consisted of two pilots and one flight engineer, two navigators (one tactical navigator and a routine navigator), one Air Electronics Officer (AEO), the sonobuoy sensor team of two Weapon System Operators (WSOp ACO) and four Weapon System Operators (WSOp EW) to manage passive and active electronic warfare systems.
Until 1992, the Nimrod MR2 was based at RAF Kinloss in Scotland (120, 201 and 206 Squadrons), and RAF St Mawgan in Cornwall (42 and 38(R) Squadrons). Following Options for Change, 42 Squadron was disbanded and its number reassigned to 38(R) Squadron. The Nimrod MR2 aircraft was withdrawn on 31 March 2010, a year earlier than planned, for financial reasons. The last official flight of a Nimrod MR2 took place on 26 May 2010, with XV229 flying from RAF Kinloss to Kent International Airport to be used as an evacuation training airframe at the nearby MOD Defence Fire Training and Development Centre.
Nimrod AEW3 XZ286 at the 1980 Farnborough Air Show
In the mid-1970s a modified Nimrod was proposed for the Airborne Early Warning (AEW) mission – again as a replacement for the Lancaster-derived, piston-engined Shackleton AEW.2. Eleven existing Nimrod airframes were to be converted by British Aerospace at the former Avro plant at Woodford to house the GEC Marconi radars in a bulbous nose and tail. The Nimrod AEW3 project was plagued by cost over-runs and problems with the GEC 4080M computer used. Eventually, the MoD recognised that the cost of developing the radar system to achieve the required level of performance was prohibitive and the probability of success very uncertain, and in December 1986 the project was cancelled. The RAF eventually received seven Boeing E-3 Sentry aircraft instead.
Nimrod MRA4 ZJ518 makes a pass with weapons bay open at the 2007 Royal International Air Tattoo
The Nimrod MRA4 was intended to replace the capability provided by the MR2. It was essentially a new aircraft, with current-generation Rolls-Royce BR710 turbofan engines, a new larger wing, and fully refurbished fuselage. However the project was subject to delays, cost over-runs, and contract re-negotiations; the type had been originally intended to enter service in 2003. The MRA4 was cancelled in 2010 as a result of the Strategic Defence and Security Review at which point it was ￡789&nbsp;million over-budget and nine years late; the development airframes were also scrapped. Some functions were dispersed to other assets, with Hercules transport aircraft and Sentry Airborne Early Warning aircraft given some tasks, but the cancellation of the MRA4 resulted in a significant gap in long-range maritime patrol and search-and rescue capability.
In July 2016, the Ministry of Defence announced the purchase of nine Boeing P-8A Poseidon aircraft for the RAF, restoring a dedicated long-range maritime patrol and reconnaissance aircraft (MPRA) capability for the United Kingdom.  These aircraft will arrive in the 2019/2020 time frame and will be based at RAF Lossiemouth.
The Nimrod was the first jet-powered maritime patrol aircraft (MPA) to enter service, being powered by the Rolls-Royce Spey turbofan engine. Aircraft in this role had been commonly propelled by piston or turboprop powerplants instead to maximise fuel economy and enable maximum patrol time on station; advantages of the Nimrod's turbofan engines included greater speed and altitude capabilities, it was also more capable of evading detection methods by submarines, whereas propeller-driven aircraft are more detectable underwater to standard acoustic sensors. Inflight, the Nimrods had a flight endurance of ten hours without aerial refuelling; the MR2s were later fitted to receive mid-air refuelling in response to demands in the Falklands War.
Pair of Nimrod R1s flying in formation, August 2004
At the start of a patrol mission all four engines would normally be running, but, as the aircraft's weight was reduced by the consumption of onboard fuel, up to two engines could be intentionally shut down, allowing the remaining engines to be operated in a more efficient manner. Instead of relying on ram air to restart an inactive engine, compressor air could be crossfed from a live engine to a starter turbine; the crossfeed duct was later discovered to be a potential fire hazard. Similarly, the two hydraulic systems on board were designed to be powered by the two inner engines that would always be running. Electrical generation was designed to far exceed the consumption of existing equipment to accommodate additional systems installed over the Nimrod's operational service.
The standard Nimrod fleet carried out three basic operational roles during their RAF service: Anti-Submarine Warfare duties typically involved surveillance over an allocated area of the North Atlantic to detect the presence of Soviet submarines in that area and to track their movements. In the event of war, reconnaissance information gathered during these patrols would be shared with other allied aircraft to enable coordinated strikes at both submarines and surface targets. Search and rescue (SAR) missions were another important duty of the RAF's Nimrod fleet, operating under the Air Rescue Coordination Centre at RAF Kinloss, and were a common sight in both military and civil maritime incidents. Throughout the Nimrod's operational life, a minimum of one aircraft was being held in a state of readiness to respond to SAR demands at all times.
Nimrod MR2 performing a low pass at Alconbury, August 1990
The Nimrod featured a large crew of up to 25 personnel, although a typical crew numbered roughly 12 members, most of which operated the various onboard sensor suites and specialist detection equipment. A significant proportion of the onboard sensor equipment was housed outside the pressure shell inside the Nimrod's distinctive pannier lower fuselage. Sensor systems included radar, sonar, and the magnetic anomaly detector; a 'sniffer' could detect exhaust fumes from diesel submarines as well. The Nimrod and its detection capabilities was an important component of Britain's military defence during the height of the Cold War.
The Nimrod's navigational functions were computerised, and were managed from a central tactical compartment housed in the forward cabin; various aircraft functions such as weapons control and information from sensors such as the large forward doppler radar were displayed and controlled at the tactical station. The flight systems and autopilot could be directly controlled by navigator's stations in the tactical compartment, giving the navigator nearly complete aircraft control. The navigational systems comprised digital, analogue, and electro-mechanical elements; the computers were directly integrated with most of the Nimrod's guidance systems such as the air data computer, astrocompass, inertial guidance and doppler radar. Navigation information could also be manually input by the operators.
Upon its introduction to service, the Nimrod was hailed as possessing advanced electronic equipment such as onboard digital computers; the increased capability of these electronic systems allowed the RAF's fleet of 46 Nimrod aircraft to provide equal coverage to that of the larger fleet of retiring Avro Shackletons. The design philosophy of these computerised systems was that of a 'man-machine partnership'; while onboard computers performed much of the data sift and analysis processes, decisions and actions on the basis of that data remained in the operator's hands. To support the Nimrod's anticipated long lifespan, onboard computers were designed to be capable of integrating with various new components, systems, and sensors that could be added in future upgrades. After a mission, gathered information could be extracted for review purposes and for further analysis.
The Nimrod featured a sizeable bomb bay in which, in addition to armaments such as torpedoes and missiles, could be housed a wide variety of specialist equipment for many purposes, such as up to 150 sonobuoys for ASW purposes or multiple air-deployed dinghies and droppable survival packs such as Lindholme Gear for SAR missions; additional fuel tanks and cargo could also be carried in the bomb bay during ferrying flights. Other armaments equippable in the bomb bay include mines, bombs, and nuclear depth charges; later munitions included the Sting Ray torpedo and Harpoon missile for increased capabilities.
The open bomb bay of a Nimrod
The Nimrod could also be fitted with two detachable pylons mounted underneath the wings to be used with missiles such as the Martel; two specialised pylons were later added to enable the equipping of Sidewinder missiles, used for self-defence purposes from hostile aircraft. A powerful remote-controlled searchlight was installed underneath the starboard wing for SAR operations. For reconnaissance missions, the aircraft was also equipped  with a pair of downward-facing cameras suited to low and high-altitude photography. In later years a newer electro-optical camera system was installed for greater imaging quality.