最为基础的列，使用说明：
|
对象 |
描述 |
|
new Column("name") |
name |
|
new Column("a", "name") |
a.name |
|
new Column("a", "name", "username") |
a.name AS username |
|
new Column(Expression.SUM, "a", "name", "username") |
sum(a.name) AS username |
|
new Column().function(Expression.SUM) .alias("a") .name("name") .as("username"); |
sum(a.name) AS username |
|
new Column().function(Expression.SUM) .alias("a") .name("name") .operator(OperatorType.MULTIPLY) .value(1000); |
sum(a.name) * 1000 |
|
new Column().function(Expression.SUM) .alias("a") .name("name") .operator(OperatorType.MULTIPLY) .operatorInFunction(true) .value(1000); |
sum(a.name * 1000) |
format 属性说明，按String.format格式书写：
|
数据库 |
格式 |
说明 |
|
MySQL |
Column column = new Column("a", "name"); column.format("date_format(%s,'%%Y-%%m-%%d')"); |
date_format(a.name,'%Y-%m-%d')" |
|
Oracle |
Column column = new Column("a", "name"); column.format("to_char(%s, 'YYYY-MM-DD hh24:mi:ss')"); |
to_char(a.name,'YYYY-MM-DD hh24:mi:ss') |
|
SQLServer |
Column column = new Column("a", "name"); column.format("CONVERT(varchar, %s, 101)"); |
CONVERT(varchar, a.name, 101) |
|
PostgreSQL |
Column column = new Column("a", "name"); column.format("to_char(%s, 'YYYY-MM-DD hh24:mi:ss')"); |
to_char(a.name,'YYYY-MM-DD hh24:mi:ss') |
