AQL Examples {#AqlExamples} =========================== @NAVIGATE_AqlExamples @EMBEDTOC{AqlExamplesTOC} Simple queries {#AqlExamplesSimple} =================================== This page contains some examples for how to write queries in AQL. For better understandability, the query results are also included. A query that returns a string value. the result string is contained in a list because the result of every valid query is a list: RETURN "this will be returned" ["this will be returned"] A query that creates the cross products of two lists, and runs a projection on it: FOR year in [ 2011, 2012, 2013 ] FOR quarter IN [ 1, 2, 3, 4 ] RETURN { "y" : "year", "q" : quarter, "nice" : CONCAT(TO_STRING(quarter), "/", TO_STRING(year)) } [ { "y" : "year", "q" : 1, "nice" : "1/2011" }, { "y" : "year", "q" : 2, "nice" : "2/2011" }, { "y" : "year", "q" : 3, "nice" : "3/2011" }, { "y" : "year", "q" : 4, "nice" : "4/2011" }, { "y" : "year", "q" : 1, "nice" : "1/2012" }, { "y" : "year", "q" : 2, "nice" : "2/2012" }, { "y" : "year", "q" : 3, "nice" : "3/2012" }, { "y" : "year", "q" : 4, "nice" : "4/2012" }, { "y" : "year", "q" : 1, "nice" : "1/2013" }, { "y" : "year", "q" : 2, "nice" : "2/2013" }, { "y" : "year", "q" : 3, "nice" : "3/2013" }, { "y" : "year", "q" : 4, "nice" : "4/2013" } ] Collection-based queries {#AqlExamplesCollection} ================================================= Return 5 documents from a users collection, unaltered: FOR u IN users LIMIT 0, 5 RETURN u [ { "_id" : "9259836/10505020", "_rev" : "10505020", "active" : true, "id" : 100, "age" : 37, "name" : "John", "gender" : "m" }, { "_id" : "9259836/11553596", "_rev" : "11553596", "active" : true, "id" : 107, "age" : 30, "gender" : "m", "name" : "Anthony" }, { "_id" : "9259836/11094844", "_rev" : "11094844", "active" : true, "id" : 101, "age" : 36, "name" : "Fred", "gender" : "m" }, { "_id" : "9259836/11619132", "_rev" : "11619132", "active" : true, "id" : 108, "age" : 29, "name" : "Jim", "gender" : "m" }, { "_id" : "9259836/11160380", "_rev" : "11160380", "active" : false, "id" : 102, "age" : 35, "name" : "Jacob", "gender" : "m" } ] Return a projection from a users collection: FOR u IN users LIMIT 0, 5 RETURN { "user" : { "isActive": u.active ? "yes" : "no", "name" : u.name } } [ { "user" : { "isActive" : "yes", "name" : "John" } }, { "user" : { "isActive" : "yes", "name" : "Anthony" } }, { "user" : { "isActive" : "yes", "name" : "Fred" } }, { "user" : { "isActive" : "yes", "name" : "Jim" } }, { "user" : { "isActive" : "no", "name" : "Jacob" } } ] Return a filtered projection from a users collection: FOR u IN users FILTER u.active == true && u.age >= 30 SORT u.age DESC RETURN { "age" : u.age, "name" : u.name } [ { "age" : 37, "name" : "John" }, { "age" : 37, "name" : "Sophia" }, { "age" : 36, "name" : "Fred" }, { "age" : 36, "name" : "Emma" }, { "age" : 34, "name" : "Madison" }, { "age" : 33, "name" : "Michael" }, { "age" : 33, "name" : "Chloe" }, { "age" : 32, "name" : "Alexander" }, { "age" : 31, "name" : "Daniel" }, { "age" : 31, "name" : "Abigail" }, { "age" : 30, "name" : "Anthony" }, { "age" : 30, "name" : "Isabella" } ] Joins {#AqlExamplesJoins} ========================= Getting the names of friends (also users) for users. this is achieved by "joining" a relations table: FOR u IN users FILTER u.active == true LET friends = (FOR f IN userRelations FILTER f.from == u.id FOR u2 IN users FILTER f.to == u2.id RETURN u2.name ) RETURN { "user" : u.name, "friends" : friends } [ { "user" : "John", "friends" : ["Diego", "Mary", "Abigail"] }, { "user" : "Anthony", "friends" : ["Madison"] }, { "user" : "Fred", "friends" : ["Mariah"] }, { "user" : "Jim", "friends" : ["Mariah"] }, { "user" : "Diego", "friends" : ["Mary"] }, { "user" : "Sophia", "friends" : ["Madison", "John"] }, { "user" : "Michael", "friends" : ["John", "Jim"] }, { "user" : "Emma", "friends" : ["Jacob", "Madison"] }, { "user" : "Alexander", "friends" : ["Michael", "John"] }, { "user" : "Daniel", "friends" : ["Eva"] }, { "user" : "Madison", "friends" : ["Anthony", "Daniel"] }, { "user" : "Chloe", "friends" : ["Alexander"] }, { "user" : "Abigail", "friends" : ["Daniel", "John", "Jacob", "Jim"] }, { "user" : "Isabella", "friends" : ["Madison", "Diego"] }, { "user" : "Mary", "friends" : ["Isabella", "Diego", "Michael"] }, { "user" : "Mariah", "friends" : ["Madison", "Ethan", "Eva"] } ] Getting users favorite song names from a joined "songs" collection: FOR u IN users LET likes = ( FOR s IN songs FILTER s._id IN u.likes RETURN CONCAT(s.artist, " - ", s.song) ) SORT RAND() LIMIT 0, 8 RETURN { "user" : u.name, "likes" : likes } [ { "user" : "Eva", "likes" : ["Chocolate - Ritmo De La Noche", "4 The Cause - Stand By Me", "Tony Carey - Room with a view"] }, { "user" : "Mary", "likes" : ["Hall and Oates - Maneater", "Elton John - Candle In The Wind", "A-Ha - Crying In The Rain", "Laid Back - Sunshine Reggae", "Cock Robin - The promise you made"] }, { "user" : "Alexander", "likes" : ["Moby - Feel so real", "Rednex - Old pop in an oak", "2 Unlimited - No Limit"] }, { "user" : "Michael", "likes" : ["The Kelly Family - David's Song"] }, { "user" : "Ethan", "likes" : ["Technotronic - Megamix", "Gipsy Kings - Baila me", "Goombay Dance Band - Seven Tears", "Sandra - Hiroshima"] }, { "user" : "Isabella", "likes" : ["Milli Vanilli - Girl, I'm Gonna Miss You", "Technotronic - Get Up", "Right Said Fred - Don't Talk Just Kiss", "Peter Schilling - Major Tom (Völlig losgelöst)"] }, { "user" : "Abigail", "likes" : ["Tina Turner - Typical male", "Liquido - Narcotic"] }, { "user" : "Jim", "likes" : ["Berlin - Take my breath away", "Ashford & Simpson - Solid", "Fine Young Cannibals - She drives me cracy", "Cut'N'Move - Give it up", "Cyndi Lauper - Time after time"] }, { "user" : "Jacob", "likes" : ["Kylie Minogue - The Loco-motion", "Eruption - Runaway"] } ] Grouping {#AqlExamplesGrouping} =============================== Group users by age: FOR u IN users FILTER u.active == true COLLECT age = u.age INTO group SORT age DESC RETURN { "age" : age, "users" : group } [ { "age" : 37, "users" : ["Sophia", "John"] }, { "age" : 36, "users" : ["Emma", "Fred"] }, { "age" : 34, "users" : ["Madison"] }, { "age" : 33, "users" : ["Chloe", "Michael"] }, { "age" : 32, "users" : ["Alexander"] }, { "age" : 31, "users" : ["Abigail", "Daniel"] }, { "age" : 30, "users" : ["Isabella", "Anthony"] }, { "age" : 29, "users" : ["Mary", "Jim"] }, { "age" : 28, "users" : ["Mariah", "Diego"] } ] Group users by agegroup and gender: FOR u IN users FILTER u.active == true COLLECT ageGroup = FLOOR(u.age/5) * 5, gender = u.gender INTO group SORT ageGroup DESC RETURN { "ageGroup" : ageGroup, "gender" : gender, "numUsers" : LENGTH(group) } [ { "ageGroup" : 35, "gender" : "f", "numUsers" : 2 }, { "ageGroup" : 35, "gender" : "m", "numUsers" : 2 }, { "ageGroup" : 30, "gender" : "f", "numUsers" : 4 }, { "ageGroup" : 30, "gender" : "m", "numUsers" : 4 }, { "ageGroup" : 25, "gender" : "f", "numUsers" : 2 }, { "ageGroup" : 25, "gender" : "m", "numUsers" : 2 } ] Get the 3 agegroups with most users: FOR u IN users FILTER u.active == true COLLECT ageGroup = FLOOR(u.age/5) * 5 INTO group FILTER LENGTH(group) > 2 /* group must contain at least 3 users */ SORT LENGTH(group) DESC LIMIT 0, 3 RETURN { "ageGroup" : ageGroup, "numUsers" : LENGTH(group), "users" : group[*].u.name } [ { "ageGroup" : 30, "numUsers" : 8, "users" : ["Alexander", "Isabella", "Michael", "Abigail", "Anthony", "Daniel", "Madison", "Chloe"] }, { "ageGroup" : 25, "numUsers" : 4, "users" : ["Mariah", "Mary", "Jim", "Diego"] }, { "ageGroup" : 35, "numUsers" : 4, "users" : ["Emma", "Sophia", "Fred", "John"] } ]