convert json to mysql table

Mysql official introduction to Insomecases, theservercreatesinternaltemporarytableswhileprocessingqueries. SuchatablecanbeheldinmemoryandprocessedbytheMEMORYstorage... mysql official introduction In some cases, the server creates internal temporary tables while processing queries. such a table can be held in memory and processed by the MEMORY storage engine, or

indexes for sorting. 6. use ENUM to replace fixed string types The ENUM column can store 65535 different strings. MySQL saves them in a very compact manner. MySQL compresses them to 1-2 bytes based on the number of values in the list, mySQL internally stores each value as an integer to indicate the position of the value in the list, and retains a "search

The company's recent MySQL always has a large number of lock tables. After analysis, it basically uses the MYISAM Table engine. A large number of reads and writes to a table by MYISAM will cause the entire MySQL table to be locked, as a result, dynamic content cannot read da

PHP failed to import JSON data into MySQL data First of all, let me make the following principles: 1, first convert the JSON into an array; 2, in the array of I need to be extracted from the data, composition I if the SQL statement part of the values, I extracted this part of an array; 3, because the above extracted va

Label:---------------------------------------------- #查询JSON的某个字段 Select data, ' $ '. Host ' from temp #创建虚拟列 ALTER TABLE temp ADD host varchar (+) GENERATED always as (json_extract (data, ' $. Host ')) VIRTUAL; #给虚拟列创建索引 ALTER TABLE temp ADD INDEX index_temp_host (host) Select COUNT (0) from temp where host>=0; 　　 ----------------------------------------------

temporary tables. If the user can write SQL statements with minimal use of internal temporary tables for query optimization, it will effectively improve the efficiency of query execution.First we define a table T1,CREATE TABLE t1( a int, b int); INSERT INTO t1 VALUES(1,2),(3,4);All of the following actions are examples based on table T1. Use sql_buffer_

#-*-coding:utf-8-*-#working with area in Excel as a Mysql INSERT statementImportxlrd, JSON, codecs, OS#data = Xlrd.open_workbook (' 101.xls ')data = Xlrd.open_workbook ('C:\Users\Administrator\Desktop\changanyiyuan.xlsx')#table = data.sheets () [0]Table =data.sheet_by_index (0)#TryHospitaljson = Codecs.open ('C:\Users\

Tags: lin system err same str method list size SchemaThis is a small fragment of a system (endowment insurance Management) that I have written about, and today it suddenly occurred to me how to change the request data to JSON. (Spring+springmvc+mybatis+mysql) as follows 1. Front-end JSP page Divclass= "Tab_tip">Please enter [ID number or name]inputtype= "text"class= "Tab_gettext"ID= "Tab1_gettext"> inputtyp

Desc View Table Structure Mysql> desc People ; +----------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------+-------------+------+-----+---------+----------------+ | ID | Int (11) | NO | PRI | NULL | auto_increment | | NAME | varchar (20) | NO | | NULL | | | Age | Int (11) | NO | | NULL | | | BIRTHDAY

normal JOIN. For example, in the following query, if t2.column1 is NULL, the WHERE clause is false: SELECT * FROM t1 LEFT JOIN t2 ON (column1) WHERE t2.column2=5; Therefore, you can safely convert a query to a normal join: SELECT * FROM t1, t2 WHERE t2.column2=5 AND t1.column1=t2.column1; This is faster, because MySQL can use table T2. To force