trigram indexes

createdb.sql

@@ -1,3 +1,5 @@
+CREATE EXTENSION pg_trgm;
+
 CREATE TABLE books (
 	id          varchar(16)  primary key,
 	title       text,
@@ -16,6 +18,20 @@ CREATE TABLE books (
 	tsv         tsvector
 );
 
+-- Books column indexes
+CREATE INDEX CONCURRENTLY books_lang_idx ON books (lang);
+CREATE INDEX CONCURRENTLY books_isbn_idx ON books (isbn);
+
+-- Books trigram indexes
+CREATE INDEX CONCURRENTLY books_title_idx ON books USING GIN (title gin_trgm_ops);
+CREATE INDEX CONCURRENTLY books_contributor_idx ON books USING GIN (contributor gin_trgm_ops);
+CREATE INDEX CONCURRENTLY books_publisher_idx ON books USING GIN (publisher gin_trgm_ops);
+CREATE FUNCTION text(text[]) RETURNS text immutable AS $$
+select $1::text
+$$ language sql;
+CREATE INDEX CONCURRENTLY books_authors_idx ON books USING GIN (text(authors) gin_trgm_ops);
+CREATE INDEX CONCURRENTLY books_tags_idx ON books USING GIN (text(tags) gin_trgm_ops);
+
 -- Books text search index
 CREATE FUNCTION books_trigger() RETURNS trigger AS $$
 declare
@@ -66,7 +82,7 @@ end
 $$ LANGUAGE plpgsql;
 CREATE TRIGGER tsvectorupdate BEFORE INSERT OR UPDATE
     ON books FOR EACH ROW EXECUTE PROCEDURE books_trigger();
-CREATE INDEX books_idx ON books USING GIN (tsv);
+CREATE INDEX CONCURRENTLY books_idx ON books USING GIN (tsv);
 
 
 CREATE TABLE news (

lib/database/books.go

@@ -48,34 +48,45 @@ func (db *pgDB) GetNewBooks(query string, length int, start int) (books []Book,
 }
 
 func (db *pgDB) getBooks(active bool, query string, length int, start int) (books []Book, num int, err error) {
-	sqlQuery := db.sql.Model(&books)
+	column := []string{}
-
+	columnParams := []interface{}{}
 	searchCondition := "active = "
 	if active {
 		searchCondition = "true"
 	} else {
 		searchCondition = "false"
 	}
+	searchParams := []interface{}{}
 
-	params := []interface{}{}
+	textQuery, columnQuerys, trigramQuerys := buildQuery(query)
-	textQuery, columnQuerys := buildQuery(query)
 	for _, c := range columnQuerys {
-		searchCondition = searchCondition + " AND " + c.column + " ILIKE ?"
+		searchCondition = searchCondition + " AND " + c.column + " = ?"
-		params = append(params, c.value)
+		searchParams = append(searchParams, c.value)
+	}
+	for _, c := range trigramQuerys {
+		column = append(column, "word_similarity(?, "+c.column+")")
+		columnParams = append(columnParams, c.value)
+		searchCondition = searchCondition + " AND " + c.column + " %> ?"
+		searchParams = append(searchParams, c.value)
 	}
 	if textQuery != "" {
+		column = append(column, "ts_rank(tsv, to_tsquery(?))")
+		columnParams = append(columnParams, textQuery)
 		searchCondition = searchCondition + " AND to_tsquery(?) @@ tsv"
-		params = append(params, textQuery)
+		searchParams = append(searchParams, textQuery)
-	}
-	sqlQuery = sqlQuery.Where(searchCondition, params...)
-
-	if textQuery != "" {
-		sqlQuery = sqlQuery.Order("ts_rank(tsv, to_tsquery(?)) DESC, upload_date DESC", textQuery)
-	} else {
-		sqlQuery = sqlQuery.Order("upload_date DESC")
 	}
 
-	num, err = sqlQuery.
+	columnStr := "*"
+	order := "upload_date DESC"
+	if len(column) > 0 {
+		columnStr = "*, " + strings.Join(column, "+") + " AS rank"
+		order = "rank DESC, upload_date DESC"
+	}
+
+	num, err = db.sql.Model(&books).
+		ColumnExpr(columnStr, columnParams...).
+		Where(searchCondition, searchParams...).
+		Order(order).
 		Offset(start).
 		Limit(length).
 		SelectAndCountEstimate(100)
@@ -157,9 +168,8 @@ type columnq struct {
 	value  string
 }
 
-func buildQuery(query string) (string, []columnq) {
+func buildQuery(query string) (textQuery string, columnQuerys []columnq, trigramQuerys []columnq) {
-	textQuery := ""
+	// FIXME: does *Querys need initialization??
-	columnQuerys := []columnq{}
 	words := strings.Split(query, " ")
 	for _, w := range words {
 		if w == "" {
@@ -169,28 +179,29 @@ func buildQuery(query string) (string, []columnq) {
 		if len(tag) > 1 && tag[1] != "" {
 			value := strings.Replace(tag[1], "%", "\\%", 0)
 			value = strings.Replace(value, "_", "\\_", 0)
-			expr := "%" + value + "%"
 			switch tag[0] {
 			case "lang":
 				columnQuerys = append(columnQuerys, columnq{"lang", value})
-			case "author":
-				columnQuerys = append(columnQuerys, columnq{"array_to_string(authors, ' ')", expr})
-			case "title":
-				columnQuerys = append(columnQuerys, columnq{"title", expr})
-			case "contributor":
-				columnQuerys = append(columnQuerys, columnq{"contributor", expr})
-			case "publisher":
-				columnQuerys = append(columnQuerys, columnq{"publisher", expr})
-			case "subject":
-				expr = strings.ToLower(expr)
-				columnQuerys = append(columnQuerys, columnq{"array_to_string(tags, ' ')", expr})
-			case "tag":
-				expr = strings.ToLower(expr)
-				columnQuerys = append(columnQuerys, columnq{"array_to_string(tags, ' ')", expr})
 			case "isbn":
-				columnQuerys = append(columnQuerys, columnq{"isbn", expr})
+				columnQuerys = append(columnQuerys, columnq{"isbn", value})
-			case "description":
+			case "author":
-				columnQuerys = append(columnQuerys, columnq{"description", expr})
+				// TODO how do we do trigram on arrays??
+				trigramQuerys = append(trigramQuerys, columnq{"array_to_string(authors, ' ')", value})
+			case "title":
+				trigramQuerys = append(trigramQuerys, columnq{"title", value})
+			case "contributor":
+				trigramQuerys = append(trigramQuerys, columnq{"contributor", value})
+			case "publisher":
+				trigramQuerys = append(trigramQuerys, columnq{"publisher", value})
+			case "subject":
+				trigramQuerys = append(trigramQuerys, columnq{"array_to_string(tags, ' ')", value})
+			case "tag":
+				trigramQuerys = append(trigramQuerys, columnq{"array_to_string(tags, ' ')", value})
+			default:
+				if len(textQuery) != 0 {
+					textQuery += " | "
+				}
+				textQuery += w
 			}
 		} else {
 			if len(textQuery) != 0 {
@@ -204,5 +215,5 @@ func buildQuery(query string) (string, []columnq) {
 			textQuery += w
 		}
 	}
-	return textQuery, columnQuerys
+	return
 }

lib/database/users.go

@@ -36,10 +36,10 @@ func (db *pgDB) AddUser(name string, pass string) error {
 		log.Error("Error hashing password: ", err)
 		return errors.New("An error happen storing the password")
 	}
-	return db.AddRawUser(name, hpass, salt, "")
+	return db.addRawUser(name, hpass, salt, "")
 }
 
-func (db *DB) AddRawUser(name string, hpass []byte, salt []byte, role string) error {
+func (db *pgDB) addRawUser(name string, hpass []byte, salt []byte, role string) error {
 	u := user{
 		Username: name,
 		Password: hpass,