Question

I am working on an app which is to suggest alternative words/phrases for input text. I have doubts about what might be a good design for the synonyms table.

Design considerations:

1. number of synonyms is variable, i.e. football has one synonym (soccer), but in particular has two (particularly, specifically)
2. if football is a synonym to soccer, the relation exists in the opposite direction as well.
3. our goal is to query a word and find its synonyms
4. we want to keep the table small and make adding new words easy

What comes to my mind is a two column design with

• col a = word and
• col b = delimited list of synonyms

Is there any better alternative? What about using two tables, one for words and the other for relations?

Edit:
After reading the answers, another approach came to my mind. It’s using a single column table with all synonym words, each wrapped in word boundary marker. With that i mean something like
|in particular|particularly|specifically|
Then I’d query the table with
SELECT * FROM synonyms WHERE word LIKE '%|specifically|%'
And in code I trash the preceding and trailing |s and do a split and have the synonyms.

Anything bad in that, that I’m not seeing?

Answer 1

After reading the answers, another approach came to my mind. It’s using a single column table with all synonym words, each wrapped in word boundary marker. With that i mean something like

|in particular|particularly|specifically|

Then I’d query the table with

SELECT * FROM `synonyms` WHERE `word` LIKE '%|$word|%'

And in code I trash the preceding and trailing |s and do an explode and have the synonyms:

$synonyms = $row['word'];
$synonyms = explode('|', substr($synonyms, 1, -1));
unset($synonyms[$word]);