background: I want to add tagging capabilities for our products. A product can have multiple tags, and each tag can be used by multiple products, which is the so-called many-to-many relationship. specific: We have 10 million products Product, admi...
what databases are used by app with a very large amount of data, such as facebook, Weibo, Jinri Toutiao and so on? how to ensure access speed? ...
Table T_USER T_ROLE : the following is the table creation and data script drop table if exists T_USER; CREATE TABLE T_USER( USER_ID INT, USER_NAME VARCHAR(25) ); INSERT INTO T_USER VALUES(1, USER_A ); INSERT INTO T_USER VALUES(2, USER_B )...
2018-04-10T08:26:03.830775Z 0 [Note] usr sbin mysqld (mysqld 5.7.20) starting as process 9836 ... 2018-04-10T08:26:03.923709Z 0 [Note] InnoDB: PUNCH HOLE support available 2018-04-10T08:26:03.923741Z 0 [Note] InnoDB: Mutexes and rw_locks use GCC atomic b...
how do you design database fields like youtube pages that show whether you have pressed like or dislike? And go to the database to judge when the user arrives at the page? whether the design idea is like this Post table id picroute likeusers dislik...
designing a complete project includes not only the front-end project design, but also the need to build local servers and databases. As a front-end developer, what kind of database should you choose? There are a lot of people around who are using mongodb...
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as shown in the figure, a simple add and query operation takes up to 1 second [environment: windows + python3 + django2]. (the amount of data in PS: is not much, and todo_list has only 2 rows of data, which is still so slow.) def get(request): -...
as shown in the figure below, does SQLAlchemy have a simple way to directly declare that the specified field is not mapped serialized? for example, does java s Hibernate framework have such a function? (although there are other "indirect " solut...
there are 200000 data in the data, and each data has a typical list of words of 5000 length [{aVl1}, {bju 2},.], and typical dictionaries of 5000 length {{aRom 1}, {bjr 2},.}, use pyMongo to find100 data, the traversal of cursor is particularly slow, is...
in sql server database, an insert trigger is set for a table, and a new view is created in the trigger. How to design and write statements? Thank you ...
for example, the isolation level of transaction An is repeatable read my understanding is that a read sql statement of transaction An is the same as the result repeated many times, regardless of whether or not other transactions have changed the data ...
my-first-vue-project@1.0.0 dev E:vuemy-first-vue-project webpack-dev-server-- inline-- progress-- config build webpack.dev.conf.js module.js:538 throw err; ^ Error: Cannot find module balanced-match at Function.Module._resolveFilename (module...
how to centralize the error_log of multiple servers after the server cluster? ...
when crawling Youdao Translation with scrapy, it is normal to return errorcode:50, with requests. def get_result(self): headers headers = { referer : https: www.baidu.com , cookie : O...
var option = { tooltip : { formatter: "{a} <br >{b} : {c}%" }, toolbox: { show : true, feature : { mark : {show: true}, restore : {show: true}, saveAsImage : {show: true} } }, series : [ { ...
as the title, there are only two pictures when walking lanterns are. I click on the first picture, click the switch on the right, switch to the second picture (no problem), click on the right again to switch to the first picture (there is a problem! ), t...