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    <p>I must say its not much clear to me what kind of example do you need. IMHO in <a href="http://docwiki.embarcadero.com/RADStudio/XE4/en/Overview_of_Attributes" rel="noreferrer">http://docwiki.embarcadero.com/RADStudio/XE4/en/Overview_of_Attributes</a> is everything you should need, perhaps providing that you have some basic knowledge of annotation and/or aspect programming resp. </p> <p>An example depends on the way/purpose an author of particular SW used attributes for. You mentioned ORM system: the typical usage here is to annotate member of class representing DB entity with additional information neccessary for DB operation in the backend of such framework. Let assume you have a DB entity having field COMPANY CHAR(32) NOT NULL and you want to represent it in Delphi class:</p> <pre><code>TSomeDBEntity = class(...) FCDS: TClientDataset; ... constructor Create; ... [TCharColumn('COMPANY', 32, false)] property CompanyName: string read GetCompanyName write SetCompanyName; end; </code></pre> <p>then you will define attribute TCharColumn with constructor</p> <pre><code>constructor TCharColumn.Create(const AFieldName:string; ALength:integer; ANullable:boolean); begin inherited; FName := AFieldName; FLength := ALength; FNullable := ANullable; end; </code></pre> <p>And usage of such annotation could look something like this:</p> <pre><code>FCDS := TClientDataset.Create(nil); RttiContext := TRttiContext.Create; try RttiType := RttiContext.GetType(self.ClassType); Props := RttiType.GetProperties; for Prop in Props do begin Attrs := Prop.GetAttributes; case Prop.PropertyType.TypeKind of tkUString: begin for Attr in Attrs do if Attr is TCharColumn then begin ColAttr := TCharColumn(Attr); FCDS.FieldDefs.Add(ColAttr.FName, ftString, ColAttr.FLength, not ColAttr.FNullable); end; end; else //... ; end; end; finally RttiContext.Free; end; </code></pre> <p>This piece of program demonstrates, how to define fields in dataset in run-time based on annotation in Delphi. We are limited little bit due lack of named parameters, hence working with parameter list is not flexible as should be e.g. like in Java (compare TMS Aurelius annotation set <a href="http://www.tmssoftware.com/site/manuals/aurelius_manual.pdf" rel="noreferrer">http://www.tmssoftware.com/site/manuals/aurelius_manual.pdf</a> and <a href="http://www.techferry.com/articles/hibernate-jpa-annotations.html" rel="noreferrer">http://www.techferry.com/articles/hibernate-jpa-annotations.html</a></p>
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    1. POWhere are the Delphi Attributes Real World Examples?
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    1. COFrom what I saw in the TMS ORM site, the code, at the beginning does not know which are the fields of the tabe, so when we use the `Create` method, the framework will read the database and allow us to type `MyString := MyORM.TableName.TableField;` and in your example you have to declare `[TCharColumn('COMPANY', 32, false)]`. Did I misunderstood the real use of the Attributes?
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    2. COTraditional approach to create DB table is to write SQL command CREATE TABLE and you operate with such table using SQL. OTOH, in ORM, you don't use SQL commands (except **where** clause). DB table is annotated class (contains attributes) and you operate data via ORM. I don't know TMS, but e.g. Hibernate on start-up checks cfg how to treat DB schema in RDBMS regarding your annotations: **validate**: production, throws exception on diff, **update**: tries update DB schema in RDBMS (not everything can be updated), **create**, **create-drop**: drops existing DB incl. data and creates new DB schema
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