如何在Anorm查询中使用'like'？

Question

My Data base is porstgres, and I am trying to write a query that will use like or ~ (postgres regex). I couldn't write this query using on.

so here is what I tried to write:

SQL(s"""SELECT id, name
       |FROM my_table 
       |WHERE name ~ '^{name}'""")
.on('name -> name).as(parser.*)

Or:

SQL(s"""SELECT id, name
       |FROM my_table 
       |WHERE name like '{name}%'""")
.on('name -> name).as(parser.*)

The code that is working for me does not use on. And it looks like this:

SQL(s"""SELECT id, name
       |FROM my_table 
       |WHERE name """.concat(s"like '$name%'").as(parser.*)

Is there a better way to achieve this?

Answer 1

When having a ... '{param}' with a string value passed using .on , the JDBC statement is prepared as ... ''$strVal'' , as the value is escaped according JDBC.

So the the single quotes should be removed from the SQL statement, and the % , must be part of the escaped string value.

SQL("""SELECT id, name
   |FROM my_table 
   |WHERE name like {name}""")
  .on('name -> s"{name}%").as(parser.*)

Moreover, there the String Interpolation is useless ( SQL(s"...") should be SQL("...") ), as Anorm placeholder are not prepared using that.

If you want to use interpolation, it would be better to use Anorm one.

SQL"""SELECT id, name
   |FROM my_table 
   |WHERE name like ${name + "%"}""".
  as(parser.*)

Answer 2

I believe the problem is that you're trying to pass a parameter to inside of a string.

What I mean is that instead of WHERE name like '{name}%' it should be just WHERE name like {name} .

SQL(s"""SELECT id, name
       |FROM my_table 
       |WHERE name like {name}""")
.on('name -> "foo%").as(parser.*)