<p>My database consists of 3 tables (one for storing all items, one for the tags, and one for the relation between the two):</p>

<p>Table: Post
Columns: PostID, Name, Desc</p>

<p>Table: Tag
Columns: TagID, Name</p>

<p>Table: PostTag
Columns: PostID, TagID</p>

<p>What is the best way to save a space separated string (e.g. "smart funny wonderful") into the 3 database tables shown above?  </p>

<p>Ultimately I would also need to retrieve the tags and display it as a string again.    Thanks!</p>

If you have a Tag Table, wouldn't you have a row for each Tag?
```
```
tag.id = 1; tag.name = 'smart'
tag.id = 2; tag.name = 'funny'
tag.id = 3; tag.name = 'wonderful'
```
```
In Groovy/Grails, you'd retrieve them as a list, possibly concatenating them into a space separated list for display.
Unless I'm really misunderstanding the question, Groovy/Grails/GORM will handle this with little or no code with the default scaffolding, no real coding required.