如何从带有squeryl的表中删除所有记录？(How can I delete all records from a table with squeryl?)

如何从带有squeryl的表中删除所有记录？(How can I delete all records from a table with squeryl?)

我已经研究了如何使用squeryl删除表中的所有记录。 我唯一能想到的就是

myTable.deleteWhere(r => r.id.isNotNull) //id is the primary key

这看起来很奇怪，也可能效率低下。

使用squeryl时从表中删除所有记录的最简洁方法是什么？

I've looked at ways to use squeryl to delete all records from a table. The only thing I could come up with is

myTable.deleteWhere(r => r.id.isNotNull) //id is the primary key

This seems strange and possibly inefficient.

What is the cleanest way to delete all records from a table when using squeryl?

最满意答案

deleteWhere子句采用任何逻辑布尔值，因此您可以简单地说：

myTable.deleteWhere(r => 1 === 1)

哪个应输出声明：

DELETE FROM mytable WHERE 1 = 1

如果要自动消除where子句，可以尝试：

myTable.deleteWhere(r => 1 === 1.inhibitWhen(true))

哪个应该完全压制where子句。

如果您正在寻找一种更有效的方法，并且您的数据库支持TRUNCATE或其他等效函数，您可以从org.squeryl.Session获取java.sql.Connection并直接通过JDBC发出查询。 不幸的是，这将失去一些Squeryl提供的类型安全性。

The deleteWhere clause takes any logical boolean, so you could simply say:

myTable.deleteWhere(r => 1 === 1)

Which should output the statement:

DELETE FROM mytable WHERE 1 = 1

If you want to eliminate the where clause automatically, you could try:

myTable.deleteWhere(r => 1 === 1.inhibitWhen(true))

Which should suppress the where clause altogether.

If you are looking for an even more efficient method and your database supports TRUNCATE or another equivalent function, you can get a java.sql.Connection from org.squeryl.Session and issue the query directly through JDBC. Unfortunately, this would lose some of the type safety Squeryl offers.