L'SQL necessario per questo è brutale; darà al tuo ottimizzatore un allenamento davvero piuttosto serio.
A giudicare dai commenti dopo la domanda così come la domanda, il desiderio è di trattare le sequenze di eventi per un dato ID utente nella tabella grande come "contigue" se rientrano tutte in un intervallo fisso tra eventi adiacenti. A titolo di esempio, l'intervallo fisso sarà di 3 ore. Sto codificando per IBM Informix Dynamic Server (per motivi di discussione, versione 11.70, ma funzionerebbe anche 11.50). Ciò significa che c'è una notazione idiosincratica che devo spiegare. In particolare, la notazione 3 UNITS HOUR denota un intervallo di 3 ore; potrebbe anche essere scritto INTERVAL(3) HOUR TO HOUR nel dialetto Informix di SQL, o come INTERVAL '3' HOUR in SQL standard.
Esistono un paio di tecniche cruciali nella generazione di SQL, in particolare SQL complesso. Uno è costruire l'SQL in più fasi, in modo frammentario, assemblando il risultato finale. L'altro è assicurarsi di avere una chiara specifica di ciò che stai cercando.
Nella notazione che segue, la qualifica 'per lo stesso User_ID' dovrebbe essere considerata come sempre parte dell'espressione.
Nella tabella grande, ci sono tre categorie di intervallo che vogliamo considerare prima di unirci alla tabella piccola.
- Voci in cui non c'è né una riga con un tempo di evento prima dell'evento che è abbastanza vicino né una riga con un tempo di evento dopo l'evento che è abbastanza vicino. Questo è un intervallo di tempo con la stessa ora di inizio e di fine.
- Una coppia di voci nella tabella che sono di per sé abbastanza vicine ma per le quali non c'è né un evento precedente all'evento iniziale della coppia che è abbastanza vicino né un evento successivo all'evento ritardato della coppia che è abbastanza vicino né un evento tra la coppia.
- Una sequenza di tre o più voci nella tabella per cui è presente:
- Nessun evento E1 precedente al primo abbastanza vicino
- Nessun evento E2 successivo all'ultimo abbastanza vicino
- Un evento E3 successivo al primo che è abbastanza vicino al primo
- Un evento E4 precedente all'ultimo che è abbastanza vicino all'ultimo (l'E4 potrebbe essere lo stesso evento dell'E3)
- Nessuna coppia di eventi E5, E6 tra il primo e l'ultimo in cui non ci sono eventi tra E5 ed E6 ma il divario tra E5 ed E6 è troppo grande per essere contato.
Come puoi vedere dalla descrizione, questo sarà un SQL spaventoso!
NB:Il codice è stato ora testato; erano necessari alcuni (soprattutto piccoli) cambiamenti. Una piccola modifica non necessaria è stata l'aggiunta delle clausole ORDER BY sulle query intermedie. Un'altra modifica non necessaria è stata quella di selezionare gli altri dati dalla piccola tabella a scopo di verifica. Questa revisione è stata effettuata senza studiare la versione modificata pubblicata da msh210 .
Nota anche che sono tutt'altro che certo che questa sia una formulazione minima; potrebbe essere possibile classificare tutti gli intervalli con una singola istruzione SELECT invece di una UNION di tre istruzioni SELECT (e se fosse così sarebbe utile).
Intervalli Singleton
-- Ranges of exactly 1 event
SELECT lt1.user_id, lt1.event_time AS min_time, lt1.event_time AS max_time
FROM Large_Table AS lt1
WHERE NOT EXISTS -- an earlier event that is close enough
(SELECT *
FROM Large_Table AS lt3
WHERE lt1.user_id = lt3.user_id
AND lt3.event_time > lt1.event_time - 3 UNITS HOUR
AND lt3.event_time < lt1.event_time
)
AND NOT EXISTS -- a later event that is close enough
(SELECT *
FROM Large_Table AS lt4
WHERE lt1.user_id = lt4.user_id
AND lt4.event_time > lt1.event_time
AND lt4.event_time < lt1.event_time + 3 UNITS HOUR
)
ORDER BY User_ID, Min_Time;
Range Doubleton
-- Ranges of exactly 2 events
SELECT lt1.user_id, lt1.event_time AS min_time, lt2.event_time AS max_time
FROM Large_Table AS lt1
JOIN Large_Table AS lt2
ON lt1.user_id = lt2.user_id
AND lt1.event_time < lt2.event_time
AND lt2.event_time < lt1.event_time + 3 UNITS HOUR
WHERE NOT EXISTS -- an earlier event that is close enough
(SELECT *
FROM Large_Table AS lt3
WHERE lt1.user_id = lt3.user_id
AND lt3.event_time > lt1.event_time - 3 UNITS HOUR
AND lt3.event_time < lt1.event_time
)
AND NOT EXISTS -- a later event that is close enough
(SELECT *
FROM Large_Table AS lt4
WHERE lt1.user_id = lt4.user_id
AND lt4.event_time > lt2.event_time
AND lt4.event_time < lt2.event_time + 3 UNITS HOUR
)
AND NOT EXISTS -- any event in between
(SELECT *
FROM Large_Table AS lt5
WHERE lt1.user_id = lt5.user_id
AND lt5.event_time > lt1.event_time
AND lt5.event_time < lt2.event_time
)
ORDER BY User_ID, Min_Time;
Aggiunto il criterio di 3 ore alla clausola WHERE esterna.
Intervalli di eventi multipli
-- Ranges of 3 or more events
SELECT lt1.user_id, lt1.event_time AS min_time, lt2.event_time AS max_time
FROM Large_Table AS lt1
JOIN Large_Table AS lt2
ON lt1.user_id = lt2.user_id
AND lt1.event_time < lt2.event_time
WHERE NOT EXISTS -- an earlier event that is close enough
(SELECT *
FROM Large_Table AS lt3
WHERE lt1.user_id = lt3.user_id
AND lt3.event_time > lt1.event_time - 3 UNITS HOUR
AND lt3.event_time < lt1.event_time
)
AND NOT EXISTS -- a later event that is close enough
(SELECT *
FROM Large_Table AS lt4
WHERE lt1.user_id = lt4.user_id
AND lt4.event_time > lt2.event_time
AND lt4.event_time < lt2.event_time + 3 UNITS HOUR
)
AND NOT EXISTS -- a gap that's too big in the events between first and last
(SELECT *
FROM Large_Table AS lt5 -- E5 before E6
JOIN Large_Table AS lt6
ON lt5.user_id = lt6.user_id
AND lt5.event_time < lt6.event_time
WHERE lt1.user_id = lt5.user_id
AND lt6.event_time < lt2.event_time
AND lt5.event_time > lt1.event_time
AND (lt6.event_time - lt5.event_time) > 3 UNITS HOUR
AND NOT EXISTS -- an event in between these two
(SELECT *
FROM Large_Table AS lt9
WHERE lt5.user_id = lt9.user_id
AND lt9.event_time > lt5.event_time
AND lt9.event_time < lt6.event_time
)
)
AND EXISTS -- an event close enough after the start
(SELECT *
FROM Large_Table AS lt7
WHERE lt1.user_id = lt7.user_id
AND lt1.event_time < lt7.event_time
AND lt7.event_time < lt1.event_time + 3 UNITS HOUR
AND lt7.event_time < lt2.event_time
)
AND EXISTS -- an event close enough before the end
(SELECT *
FROM Large_Table AS lt8
WHERE lt2.user_id = lt8.user_id
AND lt2.event_time > lt8.event_time
AND lt8.event_time > lt2.event_time - 3 UNITS HOUR
AND lt8.event_time > lt1.event_time
)
ORDER BY User_ID, Min_Time;
Aggiunta clausola NOT EXISTS nidificata omessa nella sottoquery 'big gaps'.
Tutti gli intervalli nella tabella grande
Chiaramente, l'elenco completo degli intervalli nell'ultima tabella è l'unione delle tre query precedenti.
Query eliminata perché non abbastanza interessante. È semplicemente l'UNIONE a 3 vie delle query separate sopra.
Richiesta finale
La query finale trova gli intervalli, se presenti, nel risultato della raccapricciante UNION in 3 parti che è abbastanza vicino alla voce nella piccola tabella. Una singola voce nella tabella piccola potrebbe rientrare, ad esempio, alle 13:00 e potrebbe esserci un intervallo nella tabella grande che termina alle 11:00 e un'altra che inizia alle 15:00. I due intervalli del tavolo grande sono separati (il divario tra loro è di 4 ore), ma l'ingresso nel tavolo piccolo è abbastanza vicino per entrambi da poter contare. [I test coprono questo caso. ]
SELECT S.User_id, S.Event_Time, L.Min_Time, L.Max_Time, S.Other_Data
FROM Small_Table AS S
JOIN (
-- Ranges of exactly 1 event
SELECT lt1.user_id, lt1.event_time AS min_time, lt1.event_time AS max_time
FROM Large_Table AS lt1
WHERE NOT EXISTS -- an earlier event that is close enough
(SELECT *
FROM Large_Table AS lt3
WHERE lt1.user_id = lt3.user_id
AND lt3.event_time > lt1.event_time - 3 UNITS HOUR
AND lt3.event_time < lt1.event_time
)
AND NOT EXISTS -- a later event that is close enough
(SELECT *
FROM Large_Table AS lt4
WHERE lt1.user_id = lt4.user_id
AND lt4.event_time > lt1.event_time
AND lt4.event_time < lt1.event_time + 3 UNITS HOUR
)
UNION
-- Ranges of exactly 2 events
SELECT lt1.user_id, lt1.event_time AS min_time, lt2.event_time AS max_time
FROM Large_Table AS lt1
JOIN Large_Table AS lt2
ON lt1.user_id = lt2.user_id
AND lt1.event_time < lt2.event_time
AND lt2.event_time < lt1.event_time + 3 UNITS HOUR
WHERE NOT EXISTS -- an earlier event that is close enough
(SELECT *
FROM Large_Table AS lt3
WHERE lt1.user_id = lt3.user_id
AND lt3.event_time > lt1.event_time - 3 UNITS HOUR
AND lt3.event_time < lt1.event_time
)
AND NOT EXISTS -- a later event that is close enough
(SELECT *
FROM Large_Table AS lt4
WHERE lt1.user_id = lt4.user_id
AND lt4.event_time > lt2.event_time
AND lt4.event_time < lt2.event_time + 3 UNITS HOUR
)
AND NOT EXISTS -- any event in between
(SELECT *
FROM Large_Table AS lt5
WHERE lt1.user_id = lt5.user_id
AND lt5.event_time > lt1.event_time
AND lt5.event_time < lt2.event_time
)
UNION
-- Ranges of 3 or more events
SELECT lt1.user_id, lt1.event_time AS min_time, lt2.event_time AS max_time
FROM Large_Table AS lt1
JOIN Large_Table AS lt2
ON lt1.user_id = lt2.user_id
AND lt1.event_time < lt2.event_time
WHERE NOT EXISTS -- an earlier event that is close enough
(SELECT *
FROM Large_Table AS lt3
WHERE lt1.user_id = lt3.user_id
AND lt3.event_time > lt1.event_time - 3 UNITS HOUR
AND lt3.event_time < lt1.event_time
)
AND NOT EXISTS -- a later event that is close enough
(SELECT *
FROM Large_Table AS lt4
WHERE lt1.user_id = lt4.user_id
AND lt4.event_time > lt2.event_time
AND lt4.event_time < lt2.event_time + 3 UNITS HOUR
)
AND NOT EXISTS -- a gap that's too big in the events between first and last
(SELECT *
FROM Large_Table AS lt5 -- E5 before E6
JOIN Large_Table AS lt6
ON lt5.user_id = lt6.user_id
AND lt5.event_time < lt6.event_time
WHERE lt1.user_id = lt5.user_id
AND lt6.event_time < lt2.event_time
AND lt5.event_time > lt1.event_time
AND (lt6.event_time - lt5.event_time) > 3 UNITS HOUR
AND NOT EXISTS -- an event in between these two
(SELECT *
FROM Large_Table AS lt9
WHERE lt5.user_id = lt9.user_id
AND lt9.event_time > lt5.event_time
AND lt9.event_time < lt6.event_time
)
)
AND EXISTS -- an event close enough after the start
(SELECT *
FROM Large_Table AS lt7
WHERE lt1.user_id = lt7.user_id
AND lt1.event_time < lt7.event_time
AND lt7.event_time < lt1.event_time + 3 UNITS HOUR
AND lt7.event_time < lt2.event_time
)
AND EXISTS -- an event close enough before the end
(SELECT *
FROM Large_Table AS lt8
WHERE lt2.user_id = lt8.user_id
AND lt2.event_time > lt8.event_time
AND lt8.event_time > lt2.event_time - 3 UNITS HOUR
AND lt8.event_time > lt1.event_time
)
) AS L
ON S.User_ID = L.User_ID
WHERE S.Event_Time > L.Min_Time - 3 UNITS HOUR
AND S.Event_Time < L.Max_Time + 3 UNITS HOUR
ORDER BY User_ID, Event_Time, Min_Time;
OK - giusto avviso; l'SQL non è stato effettivamente vicino a un DBMS SQL.
Il codice è stato ora testato. La possibilità infinitesimale era in realtà zero; c'era un errore di sintassi e un paio di problemi più o meno minori da risolvere.
Ho sperimentato in più fasi dopo aver ideato i dati del test. Ho utilizzato i dati "Alpha" (vedi sotto) durante la convalida e la correzione delle query e ho aggiunto i dati beta solo per assicurarmi che non vi fosse alcuna diafonia tra i diversi valori User_ID.
Ho usato < esplicito e > operazioni anziché BETWEEN ... AND escludere i punti finali; se vuoi che gli eventi a esattamente 3 ore di distanza siano considerati "abbastanza vicini", allora devi rivedere ogni disuguaglianza, possibilmente cambiandole in BETWEEN ... AND o forse semplicemente usando >= o <= a seconda dei casi.
C'è una risposta a una domanda vagamente simile ma piuttosto più semplice che (a) ho scritto e (b) ho fornito alcune riflessioni utili sulla complessa elaborazione di cui sopra (in particolare, i criteri "nessun evento prima ma abbastanza vicino" e "nessun evento dopo ma abbastanza vicino" . I criteri "abbastanza vicini" complicano decisamente questa domanda.
Dati di prova
Tavolo grande
CREATE TABLE Large_Table
(
Event_Time DATETIME YEAR TO MINUTE NOT NULL,
User_ID CHAR(15) NOT NULL,
Other_Data INTEGER NOT NULL,
PRIMARY KEY(User_ID, Event_Time)
);
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 09:15', 'Alpha', 1) { R4 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 11:15', 'Alpha', 2) { R4 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 13:15', 'Alpha', 3) { R4 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 15:15', 'Alpha', 4) { R4 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 12:17', 'Beta', 1) { R4 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-02 09:15', 'Alpha', 5) { R1 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-02 10:17', 'Beta', 2) { R1 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-03 09:15', 'Alpha', 6) { R2 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-03 11:15', 'Alpha', 7) { R2 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-03 10:17', 'Beta', 3) { R1 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-04 09:15', 'Alpha', 8) { R3 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-04 11:15', 'Alpha', 9) { R3 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-04 13:15', 'Alpha', 10) { R3 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-04 10:17', 'Beta', 4) { R1 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 09:15', 'Alpha', 11) { R2 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 11:15', 'Alpha', 12) { R2 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 10:17', 'Beta', 5) { R1 };
{ Probe here }
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 15:15', 'Alpha', 13) { R2 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 17:15', 'Alpha', 14) { R2 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 16:17', 'Beta', 6) { R1 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 09:15', 'Alpha', 15) { R6 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 11:15', 'Alpha', 16) { R6 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 13:15', 'Alpha', 17) { R6 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 15:15', 'Alpha', 18) { R6 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 17:15', 'Alpha', 19) { R6 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 19:15', 'Alpha', 20) { R6 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 16:17', 'Beta', 7) { R1 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-07 09:15', 'Alpha', 21) { R1 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-07 11:17', 'Beta', 8) { R1 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-07 12:15', 'Alpha', 22) { R1 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-07 13:17', 'Beta', 9) { R1 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-08 09:15', 'Alpha', 23) { R5 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-08 11:15', 'Alpha', 24) { R5 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-08 13:15', 'Alpha', 25) { R5 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-08 15:15', 'Alpha', 26) { R5 };
INSERT INTO Large_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-08 17:15', 'Alpha', 27) { R5 };
Tavolino
Nota:ai fini del test, la tabella piccola contiene effettivamente più righe della tabella grande. Le righe nella piccola tabella con valori Other_Data maggiori di 100 non dovrebbero apparire nei risultati (e non lo sono). I test qui colpiscono le condizioni limite.
CREATE TABLE Small_Table
(
Event_Time DATETIME YEAR TO MINUTE NOT NULL,
User_ID CHAR(15) NOT NULL,
Other_Data INTEGER NOT NULL,
PRIMARY KEY(User_ID, Event_Time)
);
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 06:15', 'Alpha', 131) { XX };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 06:20', 'Alpha', 31) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 10:20', 'Alpha', 32) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 13:20', 'Alpha', 33) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 15:20', 'Alpha', 34) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 18:15', 'Alpha', 134) { XX };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-02 06:15', 'Alpha', 135) { XX };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-02 06:16', 'Alpha', 35) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-02 10:20', 'Alpha', 35) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-02 12:14', 'Alpha', 35) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-02 12:15', 'Alpha', 135) { XX };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-03 09:20', 'Alpha', 36) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-03 11:20', 'Alpha', 37) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-04 09:20', 'Alpha', 38) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-04 11:20', 'Alpha', 39) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-04 13:20', 'Alpha', 40) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 09:20', 'Alpha', 41) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 11:20', 'Alpha', 42) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 13:20', 'Alpha', 42) { 22 };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 15:20', 'Alpha', 43) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 17:20', 'Alpha', 44) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 09:20', 'Alpha', 45) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 11:20', 'Alpha', 46) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 13:20', 'Alpha', 47) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 15:20', 'Alpha', 48) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 17:20', 'Alpha', 49) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 19:20', 'Alpha', 50) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-07 09:20', 'Alpha', 51) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-07 10:20', 'Alpha', 51) { 22 };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-07 12:20', 'Alpha', 52) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-08 09:20', 'Alpha', 53) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-08 11:20', 'Alpha', 54) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-08 13:20', 'Alpha', 55) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-08 15:20', 'Alpha', 56) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-08 17:20', 'Alpha', 57) { YY };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-07 13:27', 'Beta', 9) { R1 };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-07 11:27', 'Beta', 8) { R1 };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-06 16:27', 'Beta', 7) { R1 };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 16:27', 'Beta', 6) { R1 };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-05 10:27', 'Beta', 5) { R1 };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-04 10:27', 'Beta', 4) { R1 };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-03 10:27', 'Beta', 3) { R1 };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-02 10:27', 'Beta', 2) { R1 };
INSERT INTO Small_Table(Event_Time, User_ID, Other_Data) VALUES('2012-01-01 12:27', 'Beta', 1) { R4 };
Risultati finali della query
Utilizzando i dati sopra, i risultati ottenuti sono stati:
Alpha 2012-01-01 06:20 2012-01-01 09:15 2012-01-01 15:15 31
Alpha 2012-01-01 10:20 2012-01-01 09:15 2012-01-01 15:15 32
Alpha 2012-01-01 13:20 2012-01-01 09:15 2012-01-01 15:15 33
Alpha 2012-01-01 15:20 2012-01-01 09:15 2012-01-01 15:15 34
Alpha 2012-01-02 06:16 2012-01-02 09:15 2012-01-02 09:15 35
Alpha 2012-01-02 10:20 2012-01-02 09:15 2012-01-02 09:15 35
Alpha 2012-01-02 12:14 2012-01-02 09:15 2012-01-02 09:15 35
Alpha 2012-01-03 09:20 2012-01-03 09:15 2012-01-03 11:15 36
Alpha 2012-01-03 11:20 2012-01-03 09:15 2012-01-03 11:15 37
Alpha 2012-01-04 09:20 2012-01-04 09:15 2012-01-04 13:15 38
Alpha 2012-01-04 11:20 2012-01-04 09:15 2012-01-04 13:15 39
Alpha 2012-01-04 13:20 2012-01-04 09:15 2012-01-04 13:15 40
Alpha 2012-01-05 09:20 2012-01-05 09:15 2012-01-05 11:15 41
Alpha 2012-01-05 11:20 2012-01-05 09:15 2012-01-05 11:15 42
Alpha 2012-01-05 13:20 2012-01-05 09:15 2012-01-05 11:15 42
Alpha 2012-01-05 13:20 2012-01-05 15:15 2012-01-05 17:15 42
Alpha 2012-01-05 15:20 2012-01-05 15:15 2012-01-05 17:15 43
Alpha 2012-01-05 17:20 2012-01-05 15:15 2012-01-05 17:15 44
Alpha 2012-01-06 09:20 2012-01-06 09:15 2012-01-06 19:15 45
Alpha 2012-01-06 11:20 2012-01-06 09:15 2012-01-06 19:15 46
Alpha 2012-01-06 13:20 2012-01-06 09:15 2012-01-06 19:15 47
Alpha 2012-01-06 15:20 2012-01-06 09:15 2012-01-06 19:15 48
Alpha 2012-01-06 17:20 2012-01-06 09:15 2012-01-06 19:15 49
Alpha 2012-01-06 19:20 2012-01-06 09:15 2012-01-06 19:15 50
Alpha 2012-01-07 09:20 2012-01-07 09:15 2012-01-07 09:15 51
Alpha 2012-01-07 09:20 2012-01-07 12:15 2012-01-07 12:15 51
Alpha 2012-01-07 10:20 2012-01-07 09:15 2012-01-07 09:15 51
Alpha 2012-01-07 10:20 2012-01-07 12:15 2012-01-07 12:15 51
Alpha 2012-01-07 12:20 2012-01-07 12:15 2012-01-07 12:15 52
Alpha 2012-01-08 09:20 2012-01-08 09:15 2012-01-08 17:15 53
Alpha 2012-01-08 11:20 2012-01-08 09:15 2012-01-08 17:15 54
Alpha 2012-01-08 13:20 2012-01-08 09:15 2012-01-08 17:15 55
Alpha 2012-01-08 15:20 2012-01-08 09:15 2012-01-08 17:15 56
Alpha 2012-01-08 17:20 2012-01-08 09:15 2012-01-08 17:15 57
Beta 2012-01-01 12:27 2012-01-01 12:17 2012-01-01 12:17 1
Beta 2012-01-02 10:27 2012-01-02 10:17 2012-01-02 10:17 2
Beta 2012-01-03 10:27 2012-01-03 10:17 2012-01-03 10:17 3
Beta 2012-01-04 10:27 2012-01-04 10:17 2012-01-04 10:17 4
Beta 2012-01-05 10:27 2012-01-05 10:17 2012-01-05 10:17 5
Beta 2012-01-05 16:27 2012-01-05 16:17 2012-01-05 16:17 6
Beta 2012-01-06 16:27 2012-01-06 16:17 2012-01-06 16:17 7
Beta 2012-01-07 11:27 2012-01-07 11:17 2012-01-07 13:17 8
Beta 2012-01-07 13:27 2012-01-07 11:17 2012-01-07 13:17 9
Risultati intermedi
Formattazione leggermente diversa in vigore.
Intervalli singleton
Alpha|2012-01-02 09:15|2012-01-02 09:15
Alpha|2012-01-07 09:15|2012-01-07 09:15
Alpha|2012-01-07 12:15|2012-01-07 12:15
Beta|2012-01-01 12:17|2012-01-01 12:17
Beta|2012-01-02 10:17|2012-01-02 10:17
Beta|2012-01-03 10:17|2012-01-03 10:17
Beta|2012-01-04 10:17|2012-01-04 10:17
Beta|2012-01-05 10:17|2012-01-05 10:17
Beta|2012-01-05 16:17|2012-01-05 16:17
Beta|2012-01-06 16:17|2012-01-06 16:17
Intervalli Doubleton
Alpha|2012-01-03 09:15|2012-01-03 11:15
Alpha|2012-01-05 09:15|2012-01-05 11:15
Alpha|2012-01-05 15:15|2012-01-05 17:15
Beta|2012-01-07 11:17|2012-01-07 13:17
Intervalli di eventi multipli
Alpha|2012-01-01 09:15|2012-01-01 15:15
Alpha|2012-01-04 09:15|2012-01-04 13:15
Alpha|2012-01-06 09:15|2012-01-06 19:15
Alpha|2012-01-08 09:15|2012-01-08 17:15
