CREATE TABLE V (a varchar(255) NOT NULL, PRIMARY KEY (a)) ENGINE=MyISAM; CREATE TABLE T (a text NOT NULL, PRIMARY KEY (a(255))) ENGINE=MyISAM; I then created 200000 random strings from the alphabet [A-Z,a-z,0-9
535 character limit. In most circumstances, VARCHAR provides better performance, it’s more flexible, and can be fully indexed. If you need to store longer strings, use MEDIUMTEXT or LONGTEXT, but be aware that very large amounts of
varchar(N)中的n表示字符数,最大空间是65535个字节,存放字符数量跟字符集有关系,比如varchar(255),可以最大可存储255个汉字。如果没有要求固定长度,小于255个字符的都建议用varchar(255), 超过255个字符应结合业务考虑是否需要用text,longtext等类型 存储日期使用date类型,存储时间(精确到秒)建议使用timestamp类型,...
-- robin.logs show create table robin.logs; -- 表结构 CREATE TABLE `logs` ( `id` int(11) unsigned NOT NULL AUTO_INCREMENT, `content` text NOT NULL, `user_id` int(11) NOT NULL, `status` enum('SUCCESS','FAILED','PROCESSING') NOT NULL, `type` varchar(20) DEFAULT '', `meta` ...
mysql>CREATETABLEarticles(idINTUNSIGNEDAUTO_INCREMENTNOTNULLPRIMARYKEY,titleVARCHAR(200),bodyTEXT,FULLTEXT(title,body))ENGINE=InnoDB;mysql>INSERTINTOarticles(title,body)VALUES('MySQL Tutorial','DBMS stands for DataBase ...'),('How To Use MySQL Well','After you went through a ...'),('Optimiz...
Furthermore, bigger page sizes allow more “on page” or “inline” storage of BLOBs and large VARCHAR/TEXT fields, thus improving I/O performance when such fields are used. High Priority Transactions in InnoDB (WL#6835) : This work implements high priority transactions within InnoDB, i.e....
-longtext0-4Gb4byteoverhead 备注overhead是指需要几个字节用于记录该字段的实际长度。 从处理形态上来讲varchar 大于768字节后,实质上存储和text差别不是太大了。 基本认为是一样的。 另外从8000byte这个点说明一下: 对于varcahr, text如果行不超过8000byte(大约的数,innodb data page的一半) ,overflow不会存...
This is bad for performance, especially if the unread columns are of TEXT, LONGTEXT, 'BLOB, LONGBLOB` type as those are stored out of band, and take longer to deserialize. fixes: dolthub/dolt#8689 2795: allow using function as table function 2794: Bump go-icu-regex Incorporates the fix...
| COLUMN_NAME | varchar(64) | NO | | | | | ORDINAL_POSITION | bigint(21) unsigned | NO | | 0 | | | COLUMN_DEFAULT | longtext | YES | | NULL | | | IS_NULLABLE | varchar(3) | NO | | | | | DATA_TYPE | varchar(64) | NO | | | | ...
VARCHAR(255) can hold 255 characters. TINYTEXT can hold 255 bytes. Note the subtle difference, especially when running with utf8. This means that the former may hold more stuff. Subject Views Written By Posted VARCHAR vs. TEXT - some performance numbers ...