2009-06-28 9 views
30

mon application doit traiter les informations de calendrier (y compris les occurrences uniques, les récurrences, etc.). Afin de faciliter l'interface avec d'autres applications, j'ai pensé qu'il serait judicieux de créer mon schéma de base de données basé sur le format iCalendar (champs, relations, contraintes) directement afin d'obtenir des objets compatibles avec iCalendar via ORM. nécessaire.Liste iCalendar "Field" (pour un schéma de base de données basé sur la norme iCalendar)

Je sais que le RFC est disponible mais c'est compliqué à cause de toutes les informations supplémentaires que je n'utilise pas pour le moment. Est-ce que quelqu'un pourrait me diriger vers une source plus simple pour créer un schéma de base de données basé sur la norme iCal (c'est-à-dire une liste de champs/noms de champs et leur relation pour les entrées iCal)?

Merci!

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40

Je l'ai fait (pour VEvents seulement, ne supportant pas les éléments TODO ou les entrées de journal ou quelque chose comme ça). Ma mise en œuvre ressemble à ceci (après la suppression des colonnes qui ne sont pas spécifiques à la question):

-- One table for each event. An event may have multiple rRules. 
Create Table [vEvent] 
    (vEventID Integer Identity(1, 1) Not Null 
    Constraint [vEvent.pk] 
    Primary Key 
    Clustered 
    ,title nVarChar(200) Not Null); 

-- One table for rRules. 
-- My application does NOT support the "bySetPos" rule, so that is not included. 
Create Table [rRule] 
    (rRuleID Integer Identity(1, 1) Not Null 
    Constraint [rRule.pk] 
    Primary Key 
    Clustered 
    ,vEventID Integer Not Null 
    Constraint [fk.vEvent.rRules] 
    Foreign Key 
    References [vEvent] (vEventID) 
    On Update Cascade 
    On Delete Cascade 
    ,[class]   varChar( 12) Not Null Default('public') 
    ,[created]   DateTime  Not Null Default(getUTCDate()) 
    ,[description]  nVarChar(max)  Null 
    ,[dtStart]   DateTime  Not Null 
    ,[dtEnd]   DateTime   Null 
    ,[duration]   varChar( 20)  Null 
    ,[geoLat]   Float    Null 
    ,[geoLng]   Float    Null 
    ,[lastModified] DateTime  Not Null Default(getUTCDate()) 
    ,[location]  nVarChar(max)  Null 
    ,[organizerCN]  nVarChar( 50)  Null 
    ,[organizerMailTo] nVarChar(100)  Null 
    ,[seq]    Integer  Not Null Default(0) 
    ,[status]   varChar( 9) Not Null Default('confirmed') 
    ,[summary]   nVarChar( 75)  Null 
    ,[transparent]  Bit   Not Null Default(0) 
    ,[freq]    varChar( 8) Not Null Default('daily') 
    ,[until]   DateTime   Null 
    ,[count]   Integer   Null 
    ,[interval]  Integer  Not Null Default(1) 
    ,[bySecond]   varChar(170)  Null 
    ,[byMinute]   varChar(170)  Null 
    ,[byHour]   varChar( 61)  Null 
    ,[byDay]   varChar( 35)  Null 
    ,[byMonthDay]  varChar(200)  Null 
    ,[byYearDay]  varChar(3078)  Null 
    ,[byWeekNo]   varChar(353)  Null 
    ,[byMonth]   varChar( 29)  Null 
    ,[wkSt]    Char ( 2)  Null Default('mo')); 

-- Class must be one of "Confidential", "Private", or "Public" 
Alter Table [rRule] 
Add Constraint [rRule.ck.Class] 
Check ([class] In ('confidential', 'private', 'public')); 

-- Start date must come before End date 
Alter Table [rRule] 
Add Constraint [rRule.ck.dtStart] 
Check ([dtEnd] Is Null Or [dtStart] <= [dtEnd]); 

-- dtEnd and duration may not both be present 
Alter Table [rRule] 
Add Constraint [rRule.ck.duration] 
Check (Not ([dtEnd] Is Not Null And [duration] Is Not Null)); 

-- Check valid values for [freq]. Note that 'single' is NOT in the RFC; 
-- it is an optimization for my particular iCalendar calculation engine. 
-- I use it as a clue that this pattern has only a single date (dtStart), 
-- and there is no need to perform extra calculations on it. 
Alter Table [rRule] 
Add Constraint [rRule.ck.freq] 
Check ([freq] In 
    ('yearly' 
    ,'monthly' 
    ,'weekly' 
    ,'daily' 
    ,'hourly' 
    ,'minutely' 
    ,'secondly' 
    ,'single')); -- Single is NOT part of the spec! 

-- If there is a latitude, there must be a longitude, and vice versa. 
Alter Table [rRule] 
Add Constraint [rRule.ck.geo] 
Check (([geoLat] Is Null And [geoLng] Is Null) 
     Or ([geoLat] Is Not Null And [geoLng] Is Not Null)); 

-- Interval must be positive. 
Alter Table [rRule] 
Add Constraint [rRule.ck.interval] 
Check ([interval] > 0); 

-- Status has a set of defined values. 
Alter Table [rRule] 
Add Constraint [rRule.ck.status] 
Check ([status] In ('cancelled', 'confirmed', 'tentative')); 

-- Until and Count may not coexist in the same rule. 
Alter Table [rRule] 
Add Constraint [rRule.ck.until and count] 
Check (Not ([until] Is Not Null And [count] Is Not Null)); 


-- One table for exceptions to rRules. In my application, this covers both 
-- exDate and rDate. I do NOT support extended rule logic here; The RFC says 
-- you should support the same sort of date calculations here as are supported 
-- in rRules: exceptions can recur, etc. I don't do that; mine is simply a 
-- set of dates that are either "exceptions" (dates which don't appear, even 
-- if the rule otherwise says they should) or "extras" (dates which do appear, 
-- even if the rule otherwise wouldn't include them). This has proved 
-- sufficient for my application, and something that can be exported into a 
-- valid iCalendar file--even if I can't import an iCalendar file that makes 
-- use of recurring rules for exceptions to recurring rules. 
Create Table [exDate] 
    (exDateID Integer Identity(1, 1) Not Null 
    Constraint [exDate.pk] 
    Primary Key 
    Clustered 
    ,rRuleID Integer Not Null 
    Constraint [fk.rRule.exDates] 
    Foreign Key 
    References [rRule] (rRuleID) 
    On Update Cascade 
    On Delete Cascade 
    ,[date] DateTime Not Null 
    ,[type] varChar(6) Not Null); -- Type = "exDate" or "rDate" for me; YMMV. 

Pour aller de pair avec cela, j'ai plusieurs SQL Server 2005+ fonctions CLR qui peuvent être utilisés pour calculer les dates pour divers événements. J'ai trouvé que les formes suivantes étaient très utiles:

Select * From dbo.getDatesByVEventID(@id, @startDate, @endDate) 
Select * From dbo.getEventsByDateRange(@startDate, @endDate, @maxCount) 

La mise en œuvre de ce qui précède est un jeu d'enfant!

+0

Je sais que cela plus de 7 ans, est-ce encore la façon dont vous abordez ce, Et ne version plus récente de SQL vous donner toutes les options d'interrogation mieux? –

0

iCal est une application Apple qui suit la norme actuellement connue sous le nom d'Icalendar (le successeur du précédent Vcalendar). Je pense que le wikipedia entry a toutes les informations dont vous avez besoin pour vos besoins, et dans un format simple et facile à suivre, mais, n'hésitez pas à demander plus de conseils si nécessaire !!!

12

Oui, en quelque sorte. Sunbird (le calendrier mozilla opensource) est basé sur sqlite et je viens de télécharger et décompresser leur code source. Il contient des fichiers .sql.

ftp://ftp.mozilla.org/pub/mozilla.org/calendar/sunbird/releases/0.9/source/

mozilla \ fournisseurs calendrier de \ \ storage \ schéma 7.sql --Ce est le schéma que les usages Sunbird pour rendre les fichiers iCal valides, ne peut donc pas être trop mauvais.

1
+2

Note aux nouveaux visiteurs: Le lien de la documentation pour le développeur Apple ne fonctionne plus. –

+1

http: //www.filibeto.org/unix/macos/lib/dev/documentation/AppleApplications/Reference/SyncServicesSchemaRef/SyncServicesSchemaRef.pdf – Slartibartfast

1

Merci beaucoup Chris Nielsen pour son excellente solution ci-dessus. Cependant, j'ai eu quelques problèmes avec lui donc je l'ai modifié. S'il vous plaît noter que la solution ci-dessus est en python sqlalchemy. Je vais le convertir très bientôt.

My main difficulties with Chris's solution (and they might not apply to everyone) are 

(1) I didn't need many of the columns in his solution. I only needed columns which would help me with Events and Recurrences. This is the fault of the iCalendar spec, not Chris's. My solution below only considers recurrence rules in terms of their calendar restrictions and their sequence restrictions. 

(2) Certain columns -- most importantly dtStart and dtEnd -- belong to VEVENT, not to RRULE, but Chris placed them in RRULE. This was confusing to me. 
VEVENT: https://tools.ietf.org/html/rfc5545#section-3.6.1 
RRULE: https://tools.ietf.org/html/rfc5545#section-3.3.10 
(3) I also needed to figure out how to contain a schedule which might have a variety of patterns. For example, an event might happen every week on Friday from 6PM-9PM but also all day on May Day. This requires flexibility with dtStart and dtEnd. For this reason, I created a containing Table "SCHEDULE" which maintains a many-to-many relationship with EVENTS, whereas EVENTS have a containment relationship with RRULES. 

Below is my solution in sqlalchemy. I will convert this to SQL ASAP. 

=============================================================== 

from app import db 
from sqlalchemy import CheckConstraint 
from sqlalchemy.ext.associationproxy import association_proxy 


class Schedule(db.Model): 
    id = db.Column(db.Integer, primary_key=True) 
    subtypes_relation = db.relationship('Event', secondary=schedule_event_association, 
             backref=db.backref('Schedule', lazy='dynamic')) 

schedule_event_association = db.Table(
    'schedule_event_association', 
    db.Column('schedule_id', db.Integer, db.ForeignKey('schedule.id')), 
    db.Column('event_id', db.Integer, db.ForeignKey('event.id'))) 

class Event(db.Model): 
    id = db.Column(db.Integer, primary_key=True) 
    dt_start = db.Column(db.DateTime) # start time 
    dt_end = db.Column(db.DateTime) # end time 
    tz_id = db.Column(db.String) # Time Zone 

    recurrence_rule = db.Column('RecurrenceRule_id', db.Integer, db.ForeignKey('RecurrenceRule.id')) 

# Start date must come before End date 
    CheckConstraint('dtEnd is NULL OR dtStart <= dtEnd', name='Valid: Time Period') 

class RecurrenceRule(db.Model): 
    id = db.Column(db.Integer, primary_key=True) 

    # Frequency Type 
    freq = db.Column(db.String(8), nullable=False, default='weekly') # type of recurrence 

    # Calendar-Based Rules 
    byDay = db.Column(db.String(35)) # List of Day of the Week 
             # "mo,tu,we" for weekly 
             # "+2MO, -1MO" = second monday, last monday for yearly or monthly 
    byMonthDay = db.Column(db.String(200)) # List of Day of the Month 
              # +1,-1" 
              # Only for Monthly or Yearly 
    byYearDay = db.Column(db.String(3078)) # List Day of the Year 
              #"+1, -1" 
              # Only for yearly 
              # Take care with leap years 
    byWeekNo = db.Column(db.String(353)) # Which week of Mon`enter code here`th 
              # "+5, -3" for fifth and third-to-last 
              # Only for yearly 
    byMonth = db.Column(db.String(29)) # Month of year. 

    # Sequence-Based Rules 
    until = db.Column(db.DateTime) # last day of occurence 
    count = db.Column(db.Integer) # number of occurences 
    interval = db.Column(db.Integer, nullable=False, default=1) # interval between recurrences 
    bysetpos = db.Column(db.String()) # Specifies specific instances of recurrence 


# Valid Values 
    CheckConstraint(freq in ('yearly', 'monthly', 'weekly', 'daily', 'single'), 
        name='Valid: Frequency Value') 
    CheckConstraint(interval > 0, name='Valid: Positive Interval') 
    CheckConstraint(byDay is not None and freq in ('daily', 'yearly', 'monthly')) 
    CheckConstraint(byWeekNo is not None and freq in ('yearly', 'monthly')) 
    CheckConstraint(byYearDay is not None and freq == 'yearly') 

# Until and Count may not coexist in the same rule. 
    CheckConstraint(not (until is not None and count is not None), 
        name='Valid: Not Both Until and Count') 
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Avez-vous pu créer SQL pour cela? Je travaille sur un problème similaire et je voudrais des conseils pour le SQL. – aran

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