public class Projections extends Object
| 构造器和说明 |
|---|
Projections() |
| 限定符和类型 | 方法和说明 |
|---|---|
static Projection |
avg(String column)
聚合函数,总数avg("age") ==> avg(age)
|
static Projection |
avg(String column,
String alias)
聚合函数,总数avg("age","avgAge") ==> avg(age) AS avgAge
|
static Projection |
column(String columnName)
自定义列
|
static Projection |
column(String columnName,
String alias)
自定义列
|
static Projection |
count()
聚合函数,总数count() ==> COUNT(*)
|
static Projection |
count(String alias)
聚合函数,总数count("cnt") ==> COUNT(*) AS cnt
|
static Projection |
count(String column,
String alias)
聚合函数,总数count("id","cnt") ==> COUNT(id) AS cnt
|
static Projection |
max(String column)
聚合函数最大值,max("age") ==> max(age)
|
static Projection |
max(String column,
String alias)
聚合函数最大值,max("age","maxAge") ==> max(age) AS maxAge
|
static Projection |
min(String column)
聚合函数最小值,min("age") ==> min(age)
|
static Projection |
min(String column,
String alias)
聚合函数最小值,min("age","minAge") ==> min(age) AS minAge
|
static Projection |
sum(String column)
聚合函数总和,sum("age") ==> sum(age)
|
static Projection |
sum(String column,
String alias)
聚合函数总和,sum("age","sumAge") ==> sum(age) AS sumAge
|
public static Projection column(String columnName)
columnName - 列名,如count(*),id,等public static Projection column(String columnName, String alias)
columnName - 列名,如count(*),id,等alias - 别名public static Projection max(String column)
column - 数据库列名public static Projection max(String column, String alias)
column - 数据库列名alias - 别名public static Projection sum(String column)
column - 数据库列名public static Projection sum(String column, String alias)
column - 数据库列名alias - 别名public static Projection min(String column, String alias)
column - 数据库列名alias - 别名public static Projection min(String column)
column - 数据库列名public static Projection count(String column, String alias)
column - 列名alias - 别名public static Projection count(String alias)
alias - 别名public static Projection count()
public static Projection avg(String column, String alias)
column - 列名alias - 别名public static Projection avg(String column)
column - 列名Copyright © 2018. All Rights Reserved.