added title full text search indices for postgresql and mysql

2 files changed, 248 insertions, 7 deletions

diff --git a/askbot/search/postgresql/__init__.py b/askbot/search/postgresql/__init__.py
index 5b893129..42e10c5f 100644
--- a/askbot/search/postgresql/__init__.py
+++ b/askbot/search/postgresql/__init__.py
@@ -20,7 +20,7 @@ def setup_full_text_search(script_path):
     finally:
         cursor.close()
 
-def run_full_text_search(query_set, query_text):
+def run_full_text_search(query_set, query_text, text_search_vector_name):
     """runs full text search against the query set and
     the search text. All words in the query text are
     added to the search with the & operator - i.e.
@@ -29,14 +29,17 @@ def run_full_text_search(query_set, query_text):
     It is also assumed that we ar searching in the same
     table as the query set was built against, also
     it is assumed that the table has text search vector
-    stored in the column called `text_search_vector`.
+    stored in the column called with value of`text_search_vector_name`.
     """
     table_name = query_set.model._meta.db_table
-
+ 
     rank_clause = 'ts_rank(' + table_name + \
-        '.text_search_vector, plainto_tsquery(%s))'
-
-    where_clause = table_name + '.text_search_vector @@ plainto_tsquery(%s)'
+                    '.' + text_search_vector_name + \
+                    ', plainto_tsquery(%s))'
+ 
+    where_clause = table_name + '.' + \
+                    text_search_vector_name + \
+                    ' @@ plainto_tsquery(%s)'
 
     search_query = '&'.join(query_text.split())#apply "AND" operator
     extra_params = (search_query,)
@@ -46,5 +49,12 @@ def run_full_text_search(query_set, query_text):
         'params': extra_params,
         'select_params': extra_params,
     }
-
     return query_set.extra(**extra_kwargs)
+
+def run_thread_search(query_set, query):
+    """runs search for full thread content"""
+    return run_full_text_search(query_set, query, 'text_search_vector');
+
+def run_title_search(query_set, query):
+    """runs search for title and tags"""
+    return run_full_text_search(query_set, query, 'title_search_vector')
diff --git a/askbot/search/postgresql/thread_and_post_models_27112012.plsql b/askbot/search/postgresql/thread_and_post_models_27112012.plsql
new file mode 100644
index 00000000..9e90522d
--- /dev/null
+++ b/askbot/search/postgresql/thread_and_post_models_27112012.plsql
@@ -0,0 +1,231 @@
+/* function testing for existence of a column in a table
+   if table does not exists, function will return "false" */
+CREATE OR REPLACE FUNCTION column_exists(colname text, tablename text)
+RETURNS boolean AS 
+$$
+DECLARE
+    q text;
+    onerow record;
+BEGIN
+
+    q = 'SELECT attname FROM pg_attribute WHERE attrelid = ( SELECT oid FROM pg_class WHERE relname = '''||tablename||''') AND attname = '''||colname||''''; 
+
+    FOR onerow IN EXECUTE q LOOP
+        RETURN true;
+    END LOOP;
+
+    RETURN false;
+END;
+$$ LANGUAGE plpgsql;
+
+/* function adding tsvector column to table if it does not exists */
+CREATE OR REPLACE FUNCTION add_tsvector_column(colname text, tablename text)
+RETURNS boolean AS
+$$
+DECLARE
+    q text;
+BEGIN
+    IF NOT column_exists(colname, tablename) THEN
+        q = 'ALTER TABLE ' || tablename || ' ADD COLUMN ' || colname || ' tsvector';
+        EXECUTE q;
+        RETURN true;
+    ELSE
+        q = 'UPDATE ' || tablename || ' SET ' || colname || '=NULL';
+        EXECUTE q;
+        RETURN false;
+    END IF;
+END;
+$$ LANGUAGE plpgsql;
+
+/* aggregate function that concatenates tsvectors */
+CREATE OR REPLACE FUNCTION tsv_add(tsv1 tsvector, tsv2 tsvector)
+RETURNS tsvector AS
+$$
+BEGIN
+    RETURN tsv1 || tsv2;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE FUNCTION setup_aggregates() RETURNS boolean AS
+$$
+DECLARE
+    onerow record;
+BEGIN
+    FOR onerow IN SELECT * FROM pg_proc WHERE proname = 'concat_tsvectors' AND proisagg LOOP
+        DROP AGGREGATE concat_tsvectors(tsvector);
+    END LOOP;
+    CREATE AGGREGATE concat_tsvectors (
+        BASETYPE = tsvector,
+        SFUNC = tsv_add,
+        STYPE = tsvector,
+        INITCOND = ''
+    );
+    RETURN true;
+END;
+$$ LANGUAGE plpgsql;
+
+SELECT setup_aggregates();
+
+/* calculates text search vector for the individual thread row
+DOES not include question body post, answers or comments */
+CREATE OR REPLACE FUNCTION get_thread_tsv(title text, tagnames text)
+RETURNS tsvector AS
+$$
+BEGIN
+    /* todo add weight depending on votes */
+    RETURN  setweight(to_tsvector('english', coalesce(title, '')), 'A') ||
+            setweight(to_tsvector('english', coalesce(tagnames, '')), 'A');
+END;
+$$ LANGUAGE plpgsql;
+
+/* calculates text seanch vector for the individual question row */
+CREATE OR REPLACE FUNCTION get_post_tsv(text text, post_type text)
+RETURNS tsvector AS
+$$
+BEGIN
+    /* todo adjust weights to reflect votes */
+    IF post_type='question' THEN
+        RETURN setweight(to_tsvector('english', coalesce(text, '')), 'B');
+    ELSIF post_type='answer' THEN
+        /* todo reflect whether the answer acepted or has many points */
+        RETURN setweight(to_tsvector('english', coalesce(text, '')), 'C');
+    ELSIF post_type='comment' THEN
+        RETURN setweight(to_tsvector('english', coalesce(text, '')), 'D');
+    ELSE
+        RETURN to_tsvector('');
+    END IF;
+END;
+$$ LANGUAGE plpgsql;
+
+/* calculates text search vector for the question body part by thread id
+here we extract question title and the text by thread_id and then
+calculate the text search vector. In the future question
+title will be moved to the askbot_thread table and this function
+will be simpler.
+*/
+CREATE OR REPLACE FUNCTION get_thread_question_tsv(thread_id integer)
+RETURNS tsvector AS
+$$
+DECLARE
+    query text;
+    onerow record;
+BEGIN
+    query = 'SELECT text FROM askbot_post WHERE thread_id=' || thread_id ||
+            ' AND post_type=''question'' AND deleted=false';
+    FOR onerow in EXECUTE query LOOP
+        RETURN get_post_tsv(onerow.text, 'question');
+    END LOOP;
+    RETURN to_tsvector('');
+END;
+$$ LANGUAGE plpgsql;
+
+DROP FUNCTION IF EXISTS get_dependent_comments_tsv(object_id integer, tablename text);
+CREATE OR REPLACE FUNCTION get_dependent_comments_tsv(parent_id integer)
+RETURNS tsvector AS
+$$
+DECLARE
+    query text;
+    onerow record;
+BEGIN
+    query = 'SELECT concat_tsvectors(text_search_vector) FROM askbot_post' ||
+        ' WHERE parent_id=' || parent_id || 
+        ' AND post_type=''comment'' AND deleted=false';
+    FOR onerow IN EXECUTE query LOOP
+        RETURN onerow.concat_tsvectors;
+    END LOOP;
+    RETURN to_tsvector('');
+END;
+$$ LANGUAGE plpgsql;
+
+DROP FUNCTION IF EXISTS get_dependent_answers_tsv(question_id integer);
+CREATE OR REPLACE FUNCTION get_dependent_answers_tsv(thread_id integer)
+RETURNS tsvector AS
+$$
+DECLARE
+    query text;
+    onerow record;
+BEGIN
+    query = 'SELECT concat_tsvectors(text_search_vector) ' ||
+       'FROM askbot_post WHERE thread_id = ' || thread_id ||
+       ' AND deleted=false';
+    FOR onerow IN EXECUTE query LOOP
+        RETURN onerow.concat_tsvectors;
+    END LOOP;
+    RETURN to_tsvector('');
+END;
+$$ LANGUAGE plpgsql;
+
+/* create tsvector columns in the content tables */
+SELECT add_tsvector_column('text_search_vector', 'askbot_thread');
+SELECT add_tsvector_column('text_search_vector', 'askbot_post');
+SELECT add_tsvector_column('title_search_vector', 'askbot_thread');
+
+/* populate tsvectors with data */
+-- post tsvectors
+UPDATE askbot_post set text_search_vector = get_post_tsv(text, 'comment') WHERE post_type='comment';
+UPDATE askbot_post SET text_search_vector = get_post_tsv(text, 'answer') WHERE post_type='answer';
+UPDATE askbot_post SET text_search_vector = get_post_tsv(text, 'question') WHERE post_type='question';
+UPDATE askbot_post as q SET text_search_vector = text_search_vector ||
+    get_dependent_comments_tsv(q.id) WHERE post_type IN ('question', 'answer');
+
+--thread tsvector
+UPDATE askbot_thread SET text_search_vector = get_thread_tsv(title, tagnames);
+UPDATE askbot_thread as t SET text_search_vector = text_search_vector ||
+    get_dependent_answers_tsv(t.id) ||
+    get_thread_question_tsv(t.id);
+UPDATE askbot_thread SET title_search_vector = get_thread_tsv(title, tagnames);
+
+/* one trigger per table for tsv updates */
+
+/* set up update triggers */
+CREATE OR REPLACE FUNCTION thread_update_trigger() RETURNS trigger AS
+$$
+DECLARE
+    title_tsv tsvector;
+BEGIN
+    title_tsv = get_thread_tsv(new.title, new.tagnames);
+    new.title_search_vector = title_tsv;
+    new.text_search_vector = title_tsv ||
+                             get_thread_question_tsv(new.id) ||
+                             get_dependent_answers_tsv(new.id);
+    RETURN new;
+END;
+$$ LANGUAGE plpgsql;
+DROP TRIGGER IF EXISTS thread_search_vector_update_trigger on askbot_thread;
+CREATE TRIGGER thread_search_vector_update_trigger 
+BEFORE UPDATE ON askbot_thread FOR EACH ROW EXECUTE PROCEDURE thread_update_trigger();
+
+CREATE OR REPLACE FUNCTION thread_insert_trigger() RETURNS trigger AS
+$$
+BEGIN
+    new.text_search_vector = get_thread_tsv(new.title, new.tagnames);
+    RETURN new;
+END;
+$$ LANGUAGE plpgsql;
+DROP TRIGGER IF EXISTS thread_search_vector_insert_trigger on askbot_thread;
+CREATE TRIGGER thread_search_vector_insert_trigger
+BEFORE INSERT ON askbot_thread FOR EACH ROW EXECUTE PROCEDURE thread_insert_trigger();
+
+/* post trigger */
+CREATE OR REPLACE FUNCTION post_trigger() RETURNS trigger AS
+$$
+BEGIN
+    IF new.post_type = 'question' THEN
+        new.text_search_vector = get_post_tsv(new.text, 'question') ||
+                                 get_dependent_comments_tsv(new.id);
+    ELSIF new.post_type = 'answer' THEN
+        new.text_search_vector = get_post_tsv(new.text, 'answer') ||
+                                 get_dependent_comments_tsv(new.id);
+    ELSIF new.post_type = 'comment' THEN
+        new.text_search_vector = get_post_tsv(new.text, 'comment');
+    END IF;
+    UPDATE askbot_thread SET id=new.thread_id WHERE id=new.thread_id;
+    return new;
+END;
+$$ LANGUAGE plpgsql;
+DROP TRIGGER IF EXISTS post_search_vector_update_trigger on askbot_post;
+CREATE TRIGGER post_search_vector_update_trigger 
+BEFORE INSERT OR UPDATE ON askbot_post FOR EACH ROW EXECUTE PROCEDURE post_trigger();
+
+DROP INDEX IF EXISTS askbot_search_idx;
+CREATE INDEX askbot_search_idx ON askbot_thread USING gin(text_search_vector);