Single search box Web2py, union usage - union

Question

I am trying to create a single search box on my website.
First I split up the search input in multiple strings using split().
Then I am looping over the multiple strings I created with split(), with every string I create a query. These query's will be stored in a list.
In the next step I am trying to execute all those query's and store the results (rows) in another list.
The next thing I want to do is union all these results(rows). In this case the final result will be an output of a query containing all the different keywords used in the searchbox.
This is my code:
def ajaxlivesearch():
str = request.vars.values()[0]
a=str.split()
items = []
q = []
r =[]
for partialstr in a:
q.append((db.profiel.sport.like('%'+partialstr+'%'))|(db.profiel.speelsterkte.like('%'+partialstr+'%'))|(db.profiel.plaats.like('%'+partialstr+'%')))
for query in q:
r.append(db(query).select(groupby=db.profiel.id))
for results in r:
for (i,row) in enumerate(results):
items.append(DIV(A(B(row.id_user.first_name) ,NBSP(1), B(row.id_user.last_name),BR(), I(row.sport),I(','), NBSP(1), I(row.speelsterkte),I(','), NBSP(1),I(row.plaats),HR(), _id="res%s"%i, _href=row.id_user, _onclick="copyToBox($('#res%s').html())"%i), _id="resultLiveSearch"))
return TAG[''](*items)
My question is: How do I union the multiple results(rows)?

Answer 1

You can get the union of two Rows objects (removing duplicates) as follows:
rows_union = rows1 | rows2
However, it would be more efficient to get all the records in a single query. To simplify, you can also use the .contains method rather than using .like and wrapping each term with %s.
fields = ['sport', 'speelsterkte', 'plaats']
query_terms = [db.profiel[f].contains(term) for f in fields for term in a]
query = reduce(lambda a, b: a | b, query_terms)
results = db(query).select()
Also, you are not using any aggregation functions, so it is not clear why you have specified the groupby argument (and in any case, each record has a unique id, so grouping would have no effect). Perhaps you instead meant orderby=db.profiel.id.
Finally, it is probably not a good idea to do request.vars.values()[0], as request.vars is a dictionary-like object, and the particular value of interest is not guaranteed to be the first item in .values(). Instead, just refer to the name of the particular variable (e.g., request.vars.keyword), which is also more efficient because you are extracting a single item rather than converting all values to a list.