Elasticsearch is equivalent to a relational database
Index index
type
document document
fields
Compared with relational database
Elasticsearch is equivalent to a database
index indx ------------ equivalent to a table
type in the database type ------------- equivalent to the database Logical expression
document document ------- equivalent to a record in the database table record
field fields ------------ equivalent to a column of the table in the database
At present, the latest version has eliminated the type type 7.x. It may be used in old projects.
例子：
stu_Index
{
id:1001,
name:'hello'
}
,{
id:1001,
name:'hello'
}
The type defined by the mapping table structure is similar to the scheme defined in the database. Whether the table is the primary key can be an empty data type
NRT Near real time
Node node Each server counts as a node ES cluster
shard replica data sharding and backup
shard = primary sharde (primary
shard ) replica = replica shard (backup node)