MySql数据类型教程示例详解


1.绠瑕佹杩?/h2>

涓轰粈涔堣寮閫歁ySQL杩欎釜瀛︿範鏉垮潡鍛紵鍥犱负杩欐槸涓鍚嶆暟鎹垎鏋愬笀蹇呰鐨勪竴椤规妧鑳姐傚垎鏋愭暟鎹粈涔堟渶閲嶈锛熷綋鐒舵槸鏁版嵁锛屾棦鐒跺姝わ紒鍦ㄦ暟鎹憟鐜扮垎鍙戝紡澧為暱鐨勫勾浠o紝鎬庝箞鑳藉涓嶅瀛︽暟鎹簱鍛紵鍏跺疄杩欎篃鏄緢澶氳鑰呮湅鍙嬪笇鏈涚湅鍒扮殑锛屼篃鏄粬浠缓璁垜鍐欑殑銆?/p>

闅捐呬笉浼氾紝浼氳呬笉闅撅紒鍏跺疄缃戜笂寰堝MySQL鐨勬荤粨鏂囩珷锛屼笉鍙惁璁わ紝鐭ヨ瘑鐐瑰啓鐨勯兘寰堝叏锛屼絾鏄憿锛佽繖涓彧鏄細浣跨敤MySQL鏁版嵁搴撶殑鏈嬪弸鐨勪竴涓煡璇㈡墜鍐岋紝涓嶄細浣跨敤鐨勮繕鏄笉浼氫娇鐢ㄥ憖(骞舵病鏈夎缁嗙殑浠嬬粛)銆備簬鏄垜灏卞紑濮嬩簡鎴戣繖涓澘鍧楃殑鍐欎綔锛屽笇鏈涜兘澶熷府鍔╅偅浜涜浆琛岀殑锛岃瀛︿範MySQL鐨勬湅鍙嬩滑銆傚綋鐒惰繕瑕佽ˉ鍏呬竴鐐癸紝杩欎簺鏉垮潡骞朵笉鏄拡瀵归偅浜涙悶寮鍙戠殑銆佹兂褰揇BA鐨勬湅鍙嬶紝鑰屾槸閽堝閭d簺杞鏁版嵁鍒嗘瀽锛岀劧鍚庨渶瑕佸涔燤ySQL鏁版嵁搴撶殑閭d簺鏈嬪弸浠?/p>

鍓嶉潰鎴戜滑宸茬粡甯︾潃澶у鎬庝箞瀹夎浜哅ySQL鏁版嵁搴撲簡锛屾垜涔熺浉淇℃垜鍐欑殑杩欎釜瀹夎鏁欑▼搴旇鏄叏缃戞渶璇︾粏鐨勪竴涓暀绋嬶紝涓嶄俊浣犵湅銆?#8195;           

銆奙ySQL瀹夎鏁欑▼銆?/a>

褰撶劧锛屽鏋滀綘姝ゆ椂姝e湪涓篗ySQL鐨勪簩娆″畨瑁?绗竴娆″畨瑁呭け璐?鎰熷埌鑻︽伡锛岄偅涔堣繖涓狹ySQL鐨勫嵏杞芥枃绔犲簲璇ュ浣犱細鏈夊緢澶т綔鐢ㄣ?#8195;            

銆奙ySQL鍗歌浇鏁欑▼銆?/a>

铏界劧鎴戜滑涓嶅綋DBA锛屼絾鏄傚綋浜嗚В涓浜汳ySQL澧炲垹鏀规煡浠ュ鐨勭煡璇嗭紝涔熸槸鏈夊繀瑕佺殑锛屾瘮濡傝寤鸿〃璇彞涓轰粈涔堝姞涓婅繖涓猚harset=utf8锛熸垜浠粠杈撳叆SQL璇彞鍒版湇鍔″櫒缁欐垜浠繑鍥炴暟鎹紝绌剁珶缁忓巻浜嗕竴涓庝箞鏍风殑鍘嗙▼锛熶綘灏卞彲浠ュ疄褰撶湅鐪嬩笅闈㈣繖绡囨枃绔犮?/p>

銆婁綘鐪熺殑鎼炴槑鐧戒簡charset=utf8缂栫爜闂鍚楋紵銆?/a>

2. MySQL鏁版嵁绫诲瀷璇﹁В

瀛﹁繃缂栫▼璇█鐨勪汉閮界煡閬擄紝鎬庝箞瀛︿範涓闂ㄧ紪绋嬭瑷鍛紵棣栧厛瑕佷粠鏁版嵁绫诲瀷寮濮嬪璧枫傝櫧鐒跺簱鏄埆浜哄垱寤虹殑锛岃〃鏄埆浜鸿璁$殑锛岃繖浜涘ソ鍍忛兘涓庝綘鏃犲叧锛屼絾鏄帉鎻¤繖鏍蜂竴涓煡璇嗙偣锛屽浣犳洿濂界殑鐞嗚В鍜屽涔燤ySQL锛岃偗瀹氭槸浼氭湁甯姪鐨勩?/p>

1锛?瀛楃涓茬被鍨?/h3>

鈶?char(m)锛氬畾闀跨殑瀛楃涓层?/p>

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鈶?varchar(m)锛氫笉瀹氶暱鐨勫瓧绗︿覆銆?/p>

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涓婅堪鐭ヨ瘑锛屽彲浠ュ弬鑰冧笅鍥剧悊瑙c?/p>

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鈶?char鍜寁archar瀛樺偍鐨勭┖闂村埄鐢ㄧ巼姣旇緝銆?/p>

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浠庝笂琛ㄥ彲浠ョ湅鍑猴細

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鈶?tinytext銆乼ext銆乴ongtext

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娉ㄦ剰锛氬彧瑕佸瓨鏀剧殑鏄瓧绗︿覆绫诲瀷锛岄兘瑕佹敞鎰忕紪鐮侀棶棰橈紝涓鑸娇鐢ㄧ殑鏄痷tf8缂栫爜銆?/p>

2锛?鏁存暟绫诲瀷

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绗﹀彿浣嶄笌鏃犵鍙蜂綅璇﹁В缃戝潃锛?a target="_blank" href="https://www.jb51.net/article/178768.htm">https://www.jb51.net/article/178768.htm

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鈶?鏁村瀷鏁版嵁绫诲瀷澹版槑鏃剁殑鍙傛暟闂

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鈶?unsigned鍙傛暟銆?/p>

-- 鍒涘缓琛?
create table person(
    pname varchar(20),
    page tinyint unsigned,
    psex bit(1)
) charset=utf8;

-- 鎻掑叆涓ゆ潯璁板綍
insert into person
(pname,page,psex)
values
("寮犱笁",18,0),
("鏉庡洓",22,0);

瑙傚療涓嬪浘锛?/p>

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浠庝笂鍥惧彲浠ョ湅鍑猴細

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鈶?zerofill鍙傛暟蹇呴』鍜孧鍙傛暟閰嶅悎浣跨敤"鎵嶆湁鎰忎箟"銆?/p>

-- 瀵瑰鍙峰瓧娈佃繘琛屼竴涓鏄庯細
-- 1锛氬鍙蜂笉鑳戒负璐燂紱
-- 2锛氬鍙蜂竴鑸綅鏁扮浉鍚岋紝鍗充娇涓嶅悓锛屼篃浼氱敤0濉厖銆?
-- eg锛?0001锛?0013锛?0128锛?1280銆?
-- 鍒涘缓琛?
create table student(
    sid smallint(5) zerofill not null default 0,
    sname varchar(20),
    sage tinyint unsigned,
   ssex bit(1) default 0
) charset=utf8;

-- 鎻掑叆涓ゆ潯璁板綍
insert into student(sname,sid)
values ("寮犻",5),("鍚曞竷",1);

瑙傚療涓嬪浘锛?/p>

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浠庝笂鍥惧彲浠ョ湅鍑猴細

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3锛夋诞鐐规暟绫诲瀷

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涓句緥璇存槑锛?/p>

-- swage浠h〃宸ヨ祫锛泂bonus浠h〃娲ヨ创锛屾触璐翠笉鑳芥槸璐熸暟銆?
-- 鍒涘缓琛?
create table salary(
    sname varchar(20),
    swage float(6,2),
    sbonus float(5,2) unsigned not null default 0
) charset=utf8;

-- 鎻掑叆涓ゆ潯璁板綍
insert into salary
(sname,swage,sbonus)
values
("绾檽宀?,9999.99,111.11),
("鍜岀弲",-9999.99,444.44);

瑙傚療涓嬪浘锛?/p>

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浠庝笂鍥句腑鍙互鐪嬪嚭锛?/p>

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鈶?float/double鍜宒ecimal绮惧害姣旇緝

-- 鍒涘缓琛?
create table bank(
    id varchar(20),
    acc1 float(9,2),
    acc2 decimal(9,2)
) charset=utf8;

-- 鎻掑叆涓ゆ潯璁板綍
insert into bank(id,acc1,acc2)
values
(1,1234567.45,1234567.45),
(2,1234567.678,1234567.678);

瑙傚療涓嬭〃锛?/p>

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浠庝笂琛ㄤ腑鍙互鐪嬪嚭锛?/p>

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4锛夋棩鏈?鏃堕棿绫诲瀷

鈶?浠涔堟槸鏃ユ湡绫诲瀷鍜屾椂闂寸被鍨嬶紵

1锛夋棩鏈熺被鍨嬶細鎸囩殑鏄勾銆佹湀銆佹棩锛岀被浼间簬2019-11-16(2019骞?1鏈?6鍙?

2锛夋椂闂寸被鍨嬶細鎸囩殑鏄椂銆佸垎銆佺锛岀被浼间簬10:45:30(10鐐?5鍒?0绉?

鈶?鏃ユ湡/鏃堕棿绫诲瀷

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浠ヤ笂灏辨槸MySql鏁版嵁绫诲瀷鏁欑▼绀轰緥璇﹁В鐨勮缁嗗唴瀹癸紝鏇村鍏充簬MySql鏁版嵁绫诲瀷鐨勮祫鏂欒鍏虫敞鑴氭湰涔嬪鍏跺畠鐩稿叧鏂囩珷锛?/p>