Mysql 计算SQL连接转移成本
我有一个SQL:Mysql 计算SQL连接转移成本,mysql,join,cloud,Mysql,Join,Cloud,我有一个SQL: CREATE TABLE IF NOT EXISTS EMP ( EID varchar(4) NOT NULL PRIMARY KEY, ENAME VARCHAR(40), ESALARY DOUBLE, DID VARCHAR(4)); CREATE TABLE IF NOT EXISTS DEP ( DID varchar(4) NOT NULL PRIMARY KEY, DNAME VARCHAR(16), DLOCATION VARCHAR(30)); SELE
CREATE TABLE IF NOT EXISTS EMP (
EID varchar(4) NOT NULL PRIMARY KEY,
ENAME VARCHAR(40),
ESALARY DOUBLE,
DID VARCHAR(4));
CREATE TABLE IF NOT EXISTS DEP (
DID varchar(4) NOT NULL PRIMARY KEY,
DNAME VARCHAR(16),
DLOCATION VARCHAR(30));
SELECT * FROM EMP -> executed in T3 location
JOIN DID ON EMP.DID = DEP.DID;
EMP
在节点T1上,DEP在节点T2上
如果传输成本=大小数据
,那么如何计算执行成本: