kbmmw ORM 对象定义语法简析

使用kbmmw 的ORM 一定先要了解ORM 的对象定义语法。

下面简单说一下

// kbmMW_Table - Define a table.  定义一个表
//   Must be used on classes.
//
//   Define a table named person.
//   [kbmMW_Table('name:person')] 定义表名
//
//   Define 2 ascending indexes i_fieldname, and i_anotherfieldname on the field fieldname and anotherfieldname. 定义正向索引
//   [kbmMW_Table('name:person, index:fieldname, index:anotherfieldname...
//
//   Define an ascending index named i1, on the field name 使用索引名为一个字段定义索引
//   [kbmMW_Table('name:person, index:{name:i1,field:name},...
//
//   Define a descending index named i1, on the field name 定义反向索引
//   [kbmMW_Table('name:person, index:{name:i1,field:name,descending:true},...
//
//   Define a compound unique index named i2, on the fields name and age. Name field part is descending. 定义组合唯一索引
//   [kbmMW_Table('name:person, index:{name:i2,unique:true,fields:[{name:name,descending:true},{name:age}]
//
//   Define method to use when deleting records from a table. Default it will do a regular delete, 定义删除标志，是常规删除还是标志删除
//   but it can be set to flag the record as deleted (which is then automatically respected by
//   queries later on) or it can be set to backup the record before deletion, to another table. 
//   [kbmMW_Table('name:person, defaultDeleteMethod:delete')]  也可以定义为移动到另外一个表里面
//     defaultDeleteMethod can be delete/default, mark or move.
//     If its mark, then deleteMarkProperty must be set to point to a property or field member of the
//     class that should mark the deletion state. Futher deleteMarkValue must be set to the (non null)
//     value indicating a deleted record.
//     If its move, then deleteMoveToTable must be set to the fully scoped name of another defined
//     table, which will hold the backups. Make sure to define the table with similarly named field names.
//     Also add a different main identifier property as primary key.
//
//
// kbmMW_Field - Define fields in a table. 定义表中的字段
//   Must be used on properties within a class if they are to be persisted.
//
//   Define a field that will be persisted. Its type will be decided for
//     from the property type. String type fields will have a size of 50.
//     Table field name will be the same as the property name.
//   [kbmMW_Field] 字段标识
//
//   Define a field that will be persisted. It will accept unicode data of max 50 characters.
//     It will have the same name as the property.
//   [kbmMW_Field(ftWideString,50)] 长度为50的字符类型
//
//   Define a field named id, and make it primary key. It will be automatically populated bu the generator shortGuid.
//   [kbmMW_Field('name:id, primary:true, generator:shortGuid',ftString,40)] 定义字段名称、类型、长度，自动生成属性
//   property ID:kbmMWNullable<string> read FID write FID;
//  四种自动生成类型
//   These generators exists:
//     GUID           - Returns a GUID formatted as a regular GUID {123e4567-e89b-12d3-a456-426655440000}
//     SHORTGUID      - Returns a short GUID where braces and dashes are missing: 123e4567e89b12d3a456426655440000
//     SEQUENCE       - Returns next unique number from a sequence. Provide name of sequencer in sequence property
//                      and optional sequencestart property (not supported by all databases!)
//     DATETIME       - Returns a date time value, formatted according to the dateFormat property.


//
//   Define a field named id, and make it primary key. It will be populated by a sequence generator.
//     Since no sequencer was given, one is automatically generated named s_tablename_fieldname
//   [kbmMW_Field('name:id, primary:true, generator:sequence',ftInteger)] 定义字段为主键，并自动用序列生成
//   property ID:kbmMWNullable<integer> read FID write FID;
//
//   Define a field named id, and make it primary key. It will be populated by sequence generator SEQ, starting from value 10.
//     (not all databases supports sequencers with a defined start!) 从10开始，定义序列 
//   [kbmMW_Field('name:id, primary:true, generator:sequence, seqneuce:SEQ1, sequenceStart:10',ftInteger)]
//   property ID:kbmMWNullable<integer> read FID write FID; 属性定义，与字段名相同
//
//   Define a field named id, and make it primary key. It will be populated automatically by the database.
//     (not all databases support auto increment type fields!) 
//   [kbmMW_Field('name:id, primary:true',ftAutoInc)] 定位为自增长
//   property ID:kbmMWNullable<integer> read FID write FID;
//
//   Define a field named datetime containing date/time values as Delphi local time values.
//   [kbmMW_Field('name:datetime',ftDateTime)] 定义为日期字段
//   property DateTime:TkbmMWDateTime read FDateTime write FDateTime;
//
//   Define a field named datetime containing date/time values as Delphi UTC values.
//   [kbmMW_Field('name:datetime, dateFormat:UTC',ftDateTime)] 使用UTC 日期
//   property DateTime:TkbmMWDateTime read FDateTime write FDateTime;
//
//   Define a field named datetime containing date/time values as Unix local time millisecs since EPOC.
//   [kbmMW_Field('name:datetime, dateFormat:LOCALSINCEEPOCHMS',ftInt64)] 使用unix 当地日期，毫秒计时
//   property DateTime:TkbmMWDateTime read FDateTime write FDateTime;
//
//   Define a field named datetime containing date/time values as Unix UTC time millisecs since EPOC.
//   [kbmMW_Field('name:datetime, dateFormat:UTCSINCEEPOCHMS',ftInt64)]使用unix UTC日期，毫秒计时
//   property DateTime:TkbmMWDateTime read FDateTime write FDateTime;
//
//   Define a field named datetime containing date/time values as Unix local time secs since EPOC.
//   [kbmMW_Field('name:datetime, dateFormat:LOCALSINCEEPOCH',ftInt64)]使用unix 当地日期，秒计时
//   property DateTime:TkbmMWDateTime read FDateTime write FDateTime;
//
//   Define a field named datetime containing date/time values as Unix UTC time secs since EPOC.
//   [kbmMW_Field('name:datetime, dateFormat:UTCSINCEEPOCH',ftInt64)]使用unix TUC日期，秒计时
//   property DateTime:TkbmMWDateTime read FDateTime write FDateTime;
//
//   Define a field named datetime containing date/time values as ISO8601 formatted string.
//   [kbmMW_Field('name:datetime, dateFormat:ISO8601',ftString,50)] ISO08601 日期
//   property DateTime:TkbmMWDateTime read FDateTime write FDateTime;
//
//   Define a field named datetime containing date/time values as RFC1123 formatted string.
//   [kbmMW_Field('name:datetime, dateFormat:RFC1123',ftString,50)] RFC1123 日期
//   property DateTime:TkbmMWDateTime read FDateTime write FDateTime;
//
//   Define a field named datetime containing date/time values as NCSA formatted string.
//   [kbmMW_Field('name:datetime, dateFormat:NCSA',ftString,50)] NCSA 日期
//   property DateTime:TkbmMWDateTime read FDateTime write FDateTime;
//
// kbmMW_Null - Specify NULL conversion.
//   (This attribute is also used for object marshalling).
//
//   If, for example, a property is of type integer, the property is not directly able to indicate a NULL state since
//   all values of an integer are considered non NULL values.
//   However its possible to define a specific value to be interpreted as NULL.
//   Eg.
//   [kbmMW_Field('name:somefield',ftInteger)]
//   [kbmMW_Null(-1)] 定义-1 为空
//   property MyProperty:integer read FMyProperty write FMyProperty;
//
//   This will define that the value -1 must be interpreted as NULL when storing and retrieving data
//   from the database.
//
// kbmMW_NotNull - Indicate that the property must never contain the NULL value (either interpreted via the kbmMW_Null attribute or actual).
//   Eg.
//   [kbmMW_Field('name:somefield',ftInteger)] 字段不准为空
//   [kbmMW_NotNull]
//   property MyProperty:kbmMWNullable<integer> read FMyProperty write FMyProperty;

以下为实际的定义，请大家认真理解


   [kbmMW_Table('name:person, index:{name:i1,field:name,descending:false}, index:{name:i2,unique:true,fields:[{name:name,descending:true},{name:age}]')]
   TPerson = class
   private
      FID:kbmMWNullable<string>;
      FName:kbmMWNullable<string>;
      FAddress:kbmMWNullable<string>;
      FAge:kbmMWNullable<integer>;
   public
      [kbmMW_Field('name:id, primary:true, generator:shortGuid',ftString,40)]
      property ID:kbmMWNullable<string> read FID write FID;

      [kbmMW_Field('name:name',ftWideString,50)]
      property FullName:kbmMWNullable<string> read FName write FName;

      [kbmMW_Field('name:address',ftWideString,50)]
      property Address:kbmMWNullable<string> read FAddress write FAddress;

      [kbmMW_Field('name:age',ftInteger)]
      property Age:kbmMWNullable<integer> read FAge write FAge;
   end;

   [kbmMW_Table('name:account')]
   TAccount = class
   private
      FID:kbmMWNullable<string>;
      FPersonID:string;
      FName:kbmMWNullable<string>;
      FValue:double;
   public
      [kbmMW_Field('name:id, primary:true, generator:shortGuid',ftString,40)]
      [kbmMW_NotNull]
      property ID:kbmMWNullable<string> read FID write FID;

      [kbmMW_Field('name:personid',ftString,40)]
      [kbmMW_NotNull]
      [kbmMW_Null('')]
      property PID:string read FPersonID write FPersonID;

      [kbmMW_Field('name:name, default:"Unknown"',ftString,30)]
      [kbmMW_NotNull]
      property Name:kbmMWNullable<string> read FName write FName;

      [kbmMW_Field]
      [kbmMW_Null(Math.NaN)]
      property Value:double read FValue write FValue;
   end;

   [kbmMW_VirtualTable(TAccount)]
   TAccountWithPerson = class(TAccount)
   private
      FPerson:TPerson;
   public
      destructor Destroy; override;

      [kbmMW_VirtualField('name:person, source:uData.TPerson, key:PID, sourceKey:ID')]
      property Person:TPerson read FPerson write FPerson;
   end;

   [kbmMW_VirtualTable(TAccount)]
   TAccountWithPersonName = class(TAccount)
   private
      FFullName:kbmMWNullable<string>;
   public
//      [kbmMW_VirtualField('name:fullName, source:uData.TPerson, key:PID, sourceKey:ID, value:uData.TPerson.FullName')]
      [kbmMW_VirtualField('name:fullName, source:uData.TPerson, key:PID, sourceKey:ID, value:"uData.TPerson.FullName||" Age:"||uData.TPerson.Age"')]
      property FullName:kbmMWNullable<string> read FFullName write FFullName;
   end;

   [kbmMW_VirtualTable(TPerson)]
   TPersonWithAccounts = class(TPerson)
   private
      FAccounts:TObjectList<TAccount>;
   public
      destructor Destroy; override;

      [kbmMW_VirtualField('name:accounts, source:uData.TAccount, key:ID, sourceKey:PID')]
      property Accounts:TObjectList<TAccount> read FAccounts write FAccounts;
   end;


//   [kbmMW_Table('name:image, defaultDeleteMethod:mark, deleteMarkProperty:Deleted, deleteMarkValue:true')]
   [kbmMW_Table('name:image, defaultDeleteMethod:move, deleteMoveToTable:uData.TBackupImage')]
   TImage = class
   private
      FID:kbmMWNullable<string>;
      FDescription:kbmMWNullable<string>;
      FPersonID:string;
      FBlob:TMemoryStream;
      FDeleted:boolean;
   protected
      procedure SetBlob(AValue:TMemoryStream); virtual;
   public
      constructor Create; virtual;
      destructor Destroy; override;

      [kbmMW_Field('name:id, primary:true, generator:shortGuid',ftString,40)]
      [kbmMW_NotNull]
      property ID:kbmMWNullable<string> read FID write FID;

      [kbmMW_Field('name:personid',ftString,40)]
      [kbmMW_NotNull]
      [kbmMW_Null('')]
      property PID:string read FPersonID write FPersonID;

      [kbmMW_Field('name:description',ftString,30)]
      property Description:kbmMWNullable<string> read FDescription write FDescription;

      [kbmMW_Field('name:blob',ftGraphic)]
      [kbmMW_NotNull]
      property Blob:TMemoryStream read FBlob write SetBlob;

      [kbmMW_Field('name:deleted',ftBoolean)]
      [kbmMW_NotNull]
      property Deleted:boolean read FDeleted write FDeleted;
   end;

   [kbmMW_Table('name:backupImage')]
   TBackupImage=class(TImage)
   private
      FBackupID:kbmMWNullable<string>;

   public
//      [kbmMW_Field('name:backupId, primary:true, generator:shortGuid',ftString,40)]
//      [kbmMW_NotNull]
//      property BackupID:kbmMWNullable<string> read FBackupID write FBackupID;
//
      [kbmMW_Field('name:id, primary:true',ftString,40)]
      [kbmMW_NotNull]
      property ID:kbmMWNullable<string> read FID write FID;
   end;

   [kbmMW_VirtualTable]
   TPersonAccount = class
   private
      FID:string;
      FName,FAccountName:kbmMWNullable<string>;
      FValue:double;
   public
      [kbmMW_Field('name:id')]
      property ID:string read FID write FID;

      [kbmMW_Field('name:name')]
      property Name:kbmMWNullable<string> read FName write FName;

      [kbmMW_Field('name:accountName')]
      property AccountName:kbmMWNullable<string> read FAccountName write FAccountName;

      [kbmMW_Field('name:value')]
      property Value:double read FValue write FValue;
   end;

   [kbmMW_Table('name:person2')]
   TPerson2 = class
   private
      FID:kbmMWNullable<string>;
      FName:kbmMWNullable<string>;
      FAddress:kbmMWNullable<string>;
      FAge:kbmMWNullable<integer>;
      FAccounts:TObjectList<TAccount>;
   public
      constructor Create; virtual;
      destructor Destroy; override;

      [kbmMW_Field('name:id, primary:true, generator:shortGuid',ftString,40)]
      property ID:kbmMWNullable<string> read FID write FID;

      [kbmMW_Field('name:name',ftWideString,50)]
      property Name:kbmMWNullable<string> read FName write FName;

      [kbmMW_Field('name:address',ftWideString,50)]
      property Address:kbmMWNullable<string> read FAddress write FAddress;

      [kbmMW_Field('name:age',ftInteger)]
      property Age:kbmMWNullable<integer> read FAge write FAge;

      [kbmMW_Field('join:{source:ID,dest:PersonID}')]
      property Accounts:TObjectList<TAccount> read FAccounts;
   end;

东西真多，什么时候可以可视化设计就好了。