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kuni katsuya

UML 2 Class Diagram Guidelines - 0 views

  • UML 2 Class Diagram Guidelines
  • 1.        General Guidelines
  • 2.        Class Style Guidelines
  • ...49 more annotations...
  • Use Common Terminology for Names
  • Prefer Complete Singular Nouns for Class Names
  • Name Operations with a Strong Verb
  • Name Attributes With a Domain-Based Noun
    • kuni katsuya
       
      don't just use the attribute's type with first character lower cased!!! argghhh!  (eg. instead of Node node, Node parent)
  • Do Not Model Scaffolding Code
  • Include an Ellipsis ( … ) At The End of Incomplete Lists
  • Develop Consistent Method Signatures
  • Avoid Stereotypes Implied By Language Naming Conventions
  • 3.        Interfaces
  • Name Interfaces According To Language Naming Conventions
    • kuni katsuya
       
      I+ is NOT an acceptable naming convention!  this is a very dumb, thoughtless, pointless convention originated by microsoft
    • kuni katsuya
  • Do Not Model the Operations and Attributes of an Interface in Your Classes
  • Consider an Interface to Be a Contract
  • 4.        Relationship Guidelines
  • Model Relationships Horizontally
  • Depict Similar Relationships Involving A Common Class As A Tree
  • Always Indicate the Multiplicity
  • reduce clutter in the diagram
  • Avoid a Multiplicity of “*”
  • Replace Relationships By Indicating Attribute Types
    • kuni katsuya
       
      if dependency relationships were drawn between every class and the types of it's attributes, the class diagram becomes cluttered very quickly this dependency is obvious if the type is indicated for each attribute
  • Do Not Model Every Single Dependency
    • kuni katsuya
       
      generalization of #7 what you show/don't show depends on the main concepts  you're trying to convey in any specific diagram
  • Write Concise Association Names In Active Voice
  • Indicate Directionality To Clarify An Association Name
  • Name Unidirectional Associations In The Same Direction
  • Indicate Role Names When Multiple Associations Between Two Classes Exist
  • Indicate Role Names on Recursive Associations
    • kuni katsuya
       
      eg. parent, child
  • Make Associations Bi-Directional Only When Collaboration Occurs In Both Directions
  • Question Multiplicities Involving Minimums And Maximums
    • kuni katsuya
       
      this just leads to stupid programming practices like hard-coding array sizes, making code more brittle
  • 6.        Inheritance Guidelines
  • “is a”
  • “is like” relationships
  • Apply the Sentence Rule For Inheritance
  • Place Subclasses Below Superclasses
  • A Subclass Should Inherit Everything
    • kuni katsuya
       
      if a subclass sets an attribute to null, implements a method returning null or throwing a NotImplementedException, it really isn't a subclass, or the superclass needs to be decomposed
  • 7.        Aggregation and Composition Guidelines
  • object is made up of other objects
  • aggregation
  • “is part of” relationships
  • whole-part relationship between two objects
  • Composition
  • stronger form of aggregation where the whole and parts have
  • coincident lifetimes, and it is very common for the whole to manage the lifecycle of its parts
  • Apply the Sentence Rule for Aggregation
  • Depict the Whole to the Left of the Part
  • Don’t Worry About Getting the Diamonds Right
  • associations, aggregation, composition, dependencies, inheritance, and realizations
  • line on a UML class diagram
  • defines a cohesive set of behaviors
  • Indicate Visibility Only On Design Models
  • Design Class Diagrams Should Reflect Language Naming Conventions
kuni katsuya

Java Persistence/Relationships - Wikibooks, open books for an open world - 0 views

  • Map Key Columns (JPA 2.0)
  • Nested Collections, Maps and Matrices
  • List of Lists
  • ...58 more annotations...
  • Map of Maps,
  • Map of Lists
  • JPA does not support nested collection relationships
  • One solution is to create an object that wraps the nested collection.
  • Map<String, List<Project>>
  • Example nested collection model (original)
  • Example nested collection model (modified)
  • Map<String, ProjectType>
  • @MapKey(name="type")
  • mappedBy="employee"
  • employee
  • type;
  • List<Project>
  • ProjectType
    • kuni katsuya
       
      ProjectType wraps the original map value type List>
  • Maps J
  • JPA allows a Map to be used for any collection mapping including, OneToMany, ManyToMany and ElementCollection
  • @MapKey annotation
  • used to define a map relationship
  • @MapKey(name="type")
  • Map<String, PhoneNumber>
  • type;
  • mappedBy="owner"
  • owner
  • Map Key Columns (JPA 2.0)
  • Map Key Columns (JPA 2.0)
  • JPA 2.0 allows for a Map where the key is not part of the target object to be persisted. The Map key can be any of the following:
  • A Basic value, stored in the target's table or join table.
  • An Embedded object, stored in the target's table or join table.
  • A foreign key to another Entity, stored in the target's table or join table.
  • if the value is a Basic but the key is an Entity a
  • ElementCollection
  • mapping is used.
  • if the key is a Basic but the value is an Entity a
  • OneToMany
  • mapping is still used
  • a three way join table, can be mapped using a
  • ManyToMany with a MapKeyJoinColumn for the third foreign key
  • @MapKeyJoinColumn
  • used to define a map relationship where the
  • key is an Entity value
  • can also be used with this for composite foreign keys
  • @MapKeyClass
  • can be used when the key is an Embeddable
  • if generics are not used
  • @MapKeyColumn
  • Map<String, Phone>
  • mappedBy="owner"
  • owner
  • @MapKeyJoinColumn
  • PHONE_TYPE_ID
  • PHONE_TYPE_ID
  • Map<PhoneType, Phone>
  • mappedBy="owner"
  • owner
  • @MapKeyClass(PhoneType.class)
  • @Embeddable
  • PhoneType
  • Map<PhoneType, Phone>
  •  
    "Map Key Columns (JPA 2.0)"
kuni katsuya

Java Persistence/ManyToMany - Wikibooks, open books for an open world - 0 views

  • Bi-directional Many to Many
  • object model can choose if it will be mapped in both directions
  • in which direction it will be mapped
  • ...9 more annotations...
  • one direction must be defined as the owner and the other must use the mappedBy attribute to define its mapping
  • you will end up getting duplicate rows
  • If the mappedBy is not used, then the persistence provider will assume there are two independent relationships
  • As with all bi-directional relationships it is your object model's and application's responsibility to maintain the relationship in both direction
  • Mapping a Join Table with Additional Columns
  • solution is to create a class that models the join table
  • requires a composite primary key
  • To make your life simpler, I would recommend adding a generated Id attribute to the association class
  • Another usage is if you have a Map relationship between two objects, with a third unrelated object or data representing the Map key
    • kuni katsuya
       
      eg. map key = AuthorizationContext, map value = {Subject,Role}
kuni katsuya

Chapter 2. Mapping Entities - 0 views

  • Composite identifier
  • You can define a composite primary key through several syntaxes:
  • @EmbeddedId
  • ...66 more annotations...
  • map multiple properties as @Id properties
  • annotated the property as
  • map multiple properties as @Id properties and declare an external class to be the identifier type
  • declared on the entity via the @IdClass annotation
  • The identifier type must contain the same properties as the identifier properties of the entity: each property name must be the same, its type must be the same as well if the entity property is of a
  • basic type
  • last case is far from obvious
  • recommend you not to use it (for simplicity sake)
  • @EmbeddedId property
  • @EmbeddedId
  • @Embeddable
  • @EmbeddedId
  • @Embeddable
  • @Embeddable
  • @EmbeddedId
  • Multiple @Id properties
  • arguably more natural, approach
  • place @Id on multiple properties of my entity
  • only supported by Hibernate
  • does not require an extra embeddable component.
  • @IdClass
  • @IdClass on an entity points to the class (component) representing the identifier of the class
  • WarningThis approach is inherited from the EJB 2 days and we recommend against its use. But, after all it's your application and Hibernate supports it.
  • Mapping entity associations/relationships
  • One-to-one
  • three cases for one-to-one associations:
  • associated entities share the same primary keys values
  • foreign key is held by one of the entities (note that this FK column in the database should be constrained unique to simulate one-to-one multiplicity)
  • association table is used to store the link between the 2 entities (a unique constraint has to be defined on each fk to ensure the one to one multiplicity)
  • @PrimaryKeyJoinColumn
  • shared primary keys:
  • explicit foreign key column:
  • @JoinColumn(name="passport_fk")
  • foreign key column named passport_fk in the Customer table
  • may be bidirectional
  • owner is responsible for the association column(s) update
  • In a bidirectional relationship, one of the sides (and only one) has to be the owner
  • To declare a side as
  • not responsible for the relationship
  • the attribute
  • mappedBy
  • is used
  • mappedBy
  •  Indexed collections (List, Map)
  • Lists can be mapped in two different ways:
  • as ordered lists
  • as indexed lists
  • @OrderBy("number")
  • List<Order>
  • List<Order>
  • List<Order> 
  • To use one of the target entity property as a key of the map, use
  • @MapKey(name="myProperty")
  •  @MapKey(name"number")
  • Map<String,Order>
  • String number
    • kuni katsuya
       
      map key used in Customer.orders
  • @MapKeyJoinColumn/@MapKeyJoinColumns
  • if the map key type is another entity
  • @ManyToAny
  • 2.4.5.2. @Any
  • @Any annotation defines a polymorphic association to classes from multiple tables
  • this is most certainly not meant as the usual way of mapping (polymorphic) associations.
  • @ManyToAny allows polymorphic associations to classes from multiple tables
  • first column holds the type of the associated entity
  • remaining columns hold the identifier
  • not meant as the usual way of mapping (polymorphic) associations
kuni katsuya

UML Association - relationship between classifiers to show that instances of classifier... - 0 views

  • UML Association
  • Aggregation
  • aggregation
  • ...28 more annotations...
  • composition
  • shared aggregation
  • composite aggregation
  • (shared) part could be included in several composites
  • if composite is deleted, shared parts may still exist.
  • hollow diamond
  • Composition
  • "strong" form of aggregation.
  • "weak" form of aggregation
  • whole/part relationship,
  • composite (whole) is deleted, all of its composite parts are "normally" deleted with it.
  • aggregation
  • Aggregation
  • "weak" form of aggregation
  • composite aggregation
  • composition
  • shared aggregation (
  • same (shared) part could be included in several composites
  • composite is deleted, shared parts may still exist.
  • hollow diamond a
  • Composition
  • "strong" form of aggregation
  • part could be included in at most one composite
  • whole/part relationship,
  • composite (whole) is deleted, all of its composite parts are "normally" deleted with it.
  • filled black diamond
  • N-ary Association
  • more than two ends can only be drawn this way.
kuni katsuya

Java Persistence/Inheritance - Wikibooks, open books for an open world - 0 views

  • Inheritance
  • hardest part of persisting inheritance is choosing how to represent the inheritance in the database
  • There are three inheritance strategies defined from the InheritanceType enum,
  • ...101 more annotations...
  • SINGLE_TABLE
  • TABLE_PER_CLASS
  • JOINED
  • Single table inheritance is the default
  • @MappedSuperclass
  • @Inheritance
  • mapped superclass is
  • not a persistent class
  • but allow common mappings to be define for its subclasses
  • Single Table Inheritance
    • kuni katsuya
       
      implemented as a sparse table. ie. all attributes from all entities end up as columns in the 'super' table
  • single table is used to store all of the instances of the entire inheritance hierarchy
  • table will have a column for
  • every attribute
  • every class
  • in the hierarchy
  • discriminator column
  • is used to determine which class the particular row belongs to
  • abstract
  • Project
  • extends Project
  • extends Project
  • @DiscriminatorValue("S")
  • @DiscriminatorValue("L")
  • @DiscriminatorColumn(name="PROJ_TYPE")
  • @Inheritance
  • @Table(name="PROJECT")
  • single table inheritance
  • Joined, Multiple Table Inheritance
  • mirrors the object model in the data model
  • table is defined for each class in the inheritance hierarchy to store only the local attributes of that class
  • Each table in the hierarchy must also store the object's id (primary key), which is
  • only defined in the root class
  • share the same id attribute
  • joined inheritance
  • @Inheritance(strategy=
  • InheritanceType.JOINED
  • @DiscriminatorColumn(name="PROJ_TYPE")
  • @Table(name="PROJECT")
  • abstract
  • Project
  • @DiscriminatorValue("L")
  • @Table(name=
  • "LARGEPROJECT"
  • LargeProject
  • Project
  • @DiscriminatorValue("S")
  • @Table(name=
  • "SMALLPROJECT"
  • SmallProject
  • Project
  • Table Per Class Inheritance
  • Advanced
  • table is defined for
  • each concrete class
  • in the inheritance hierarchy to store
  • all the attributes
  • of that class and
  • all of its superclasses
  • table per class inheritance
  • @Inheritance(strategy=
  • InheritanceType.TABLE_PER_CLASS
  • abstract
  • Project
  • @Table(name="LARGEPROJECT")
  • LargeProject
  • Project
  • @Table(name="SMALLPROJECT")
  • SmallProject
  • Project
  • Mapped Superclasses
  • similar to table per class inheritance, but does not allow querying, persisting, or relationships to the superclass
  • mapped superclass
  • @MappedSuperclass
  • abstract
  • Project
  • @Column(name="NAME")
  • @Table(name="LARGEPROJECT")
  • LargeProject
  • Project
  • @AttributeOverride
  • "PROJECT_NAME"
  • "name"
  • @Table("SMALLPROJECT")
  • SmallProject
  • Project
  • cannot have a relationship to a mapped superclass
  • Joined, Multiple Table Inheritance
  • oined, Multiple Table Inheritance
  • abstract
  • abstract c
  • extends Project
  • Mapped Superclasses
  • Mapped Superclasses
  • apped Superclasses
  • allows inheritance to be used in the object model, when it does not exist in the data model
  • @MappedSuperclass
  • MappedSuperclass
  • abstract
  • abstract
  • extends Project
  • extends Project
kuni katsuya

TH02-EP02-US004 - VFML Admin, Org Mgmt, Sync Properties - Projects - Confluence - 0 views

  • using EXCC
    • kuni katsuya
       
      why is excc required as the mechanism?
  • sync properties
    • kuni katsuya
       
      sync meaning: a. ensuring that chain-hotel relationships based on icpm data is represented the same way in the cube node structure? (eg. which hotels belong under which chains, and to keep dynamically/automatically updated as hotels are added/removed from chains) 2. or...?
  • As a VFML user
    • kuni katsuya
       
      implies restriction of this action via authorization controls (ie. required vs granted permissions)
  • ...1 more annotation...
  • maintain an accurate listing of properties in an org
    • kuni katsuya
       
      ie. cube node-org-chain tree reflects icpm relationships exactly & always
kuni katsuya

Supported Place Types - Google Places API (Experimental) - Google Developers - 0 views

  • Place Types
  • Google Places API
  • supported types for Place searches and Place adds
  • ...30 more annotations...
  • Additional types listed in table #2 can be used when searching for a Place,
  • but not when adding a Place
    • kuni katsuya
       
      so, not treated as a 'full-blown' place type(?) in cube domain model, would this be similar to relationship between hotel ('primary' subject type) and neighborhood ('secondary' subject type, since content can be attached to it, but it would never 'drive' of this relationship)
  • airport
  • amusement_park
  • art_gallery
  • shopping_mall
  • restaurant
  • museum
  • night_club
  • place_of_worship
  • train_station
  • lodging
  • hospital
  • These types cannot be used when adding a new Place
  • floor
  • geocode
  • intersection
  • locality
  • neighborhood
  • point_of_interest
  • postal_code
  • postal_code_prefix
  • route
  • street_address
  • street_number
  • sublocality
  • subpremise
  • country
  • administrative_area_level_1 administrative_area_level_2 administrative_area_level_3
  • premise
kuni katsuya

Java Persistence/Relationships - Wikibooks, open books for an open world - 0 views

  • Cascading
  • following operations can be cascaded, as defined in the CascadeType enum:
  • PERSIST
  • ...11 more annotations...
  • If persist() is called on the
  • parent
  • and the
  • child
  • is also new, it will also be persisted
  • MERGE
  • REFRESH
  • REMOVE
  • . If remove() is called on the parent then the child will also be removed
  • . If merge() is called on the parent, then the child will also be merged
  • If refresh() is called on the parent then the child will also be refreshed
kuni katsuya

Hibernate - Many-to-Many example - join table + extra column (Annotation) - 0 views

  • Many-to-Many example – join table + extra column (Annotation)
  • For many to many relationship with
  • NO extra column in the join table
  • ...1 more annotation...
  • please refer to this @many-to-many tutorial
kuni katsuya

mysql - Relationship between catalog, schema, user, and database instance - Stack Overflow - 0 views

kuni katsuya

Graph database - Wikipedia, the free encyclopedia - 0 views

  • are pertinent information that relate to nodes
    • kuni katsuya
       
      ie. attributes of the entities (aka nodes)
  • Edges
  • are the lines that connect
  • ...6 more annotations...
  • nodes to nodes
  • nodes to properties
  • they represent the relationship between the two
  • Most of the important information is really stored in the edges
  • depend less on a rigid schema, they are more suitable to manage ad-hoc and changing data with evolving schemas
  • Conversely, relational databases are typically faster at performing the same operation on large numbers of data elements
kuni katsuya

JPA/Hibernate Ternary Association « Fulvio Di Marco: just a personal code not... - 0 views

  • JPA/Hibernate Ternary Association
  •  
    "JPA/Hibernate Ternary Association"
kuni katsuya

Enterprise Architect - Product Demonstrations - 0 views

  • Part 2 Subversion Setting up a Subversion repository for use with Enterprise Architect models.
  • Part 4 Configure & Connect Configuring Enterprise Architect and connecting to your Version Control system.
  • Part 5 Controlled Packages Working with version controlled UML packages in Enterprise Architect.
  • ...19 more annotations...
  • Eclipse A tour of MDG Integration for Eclipse.
  • Baseline Diagram Comparison Conduct a visual diagram comparison between your current diagram and a previous baseline .
  • Personal Information Window See how the Personal Information Window in Enterprise Architect can help you organize your daily tasks and workflow.
  • Working Sets As you perform work on your model, you open various windows, diagrams and views. Working Sets allow you to return to these same views in a later work session.
  • Business Rules A car rental system is used to illustrate how to generate executable business rules using Enterprise Architect.
  • Menu Customization Quickly and easily suppress individual menu items or entire categories of commands to create custom menu layouts.
  • Floating and Dockable Windows Save the position and layout of Floating and Dockable Windows using a Working Set in the Personal Information Window.
  • Build and Debug a Java Application Set up Enterprise Architect to build and debug a Java Application, using a VEA sample project.
  • Sequence Diagrams Learn how to create a simple Sequence diagram. The video also illustrates how to bring your Sequence diagram to life using model simulation.
  • HTML Report Generation This brief introduction illustrates how to automatically generate a HTML Report using Enterprise Architect.
  • Basic Use Case Demonstration A guide to constructing a Use Case model in under 30 seconds, including use cases, notes and issues.
  • Traceability within Enterprise Architect This video examines Traceability and discusses how to use Enterprise Architect to conduct an Impact Analysis.
  • Requirements Reporting A brief overview of requirements reporting in Enterprise Architect. Topics include document generation in web and RTF formats, report customization and virtual documents, including Model and Master documents.
  • Requirements Traceability An examination of requirements traceability in Enterprise Architect. Topics include traceability views, tracing to external artifacts, conducting an impact analysis, viewing the Relationship Matrix and using Enterprise Architect's Auditing capabilities.
  • Requirements Modeling A brief overview of requirements modeling in Enterprise Architect. Topics include requirements capture and definition, custom properties, tabular editing, auto-naming and screen prototypes.
  • Installing EA An introductory walk through and discussion of Enterprise Architect in the Software Development Lifecycle.
  • Enterprise Architect 7.5 Overview An overview of Enterprise Architect features released with version 7.5.
  • Introduction to Enterprise Architect An introductory walk through and discussion of Enterprise Architect in the Software Development Lifecycle.
  • Brief Overview The 10 minute guide to Enterprise Architect, from Requirements Management and Business Process Modeling to MDA and Code Engineering.
kuni katsuya

Enterprise Architect - Resources - Model Driven Generation (MDG) Technologies - 0 views

  • Model Driven Generation (MDG) Technologies
  • MDG Technologies allow users to extend Enterprise Architect's modeling capabilities to specific domains and notations. MDG Technologies seamlessly plug into Enterprise Architect to provide additional toolboxes, UML profiles, patterns, templates and other modeling resources.
  • Free MDG Technology downloads for Enterprise Architect:
  • ...12 more annotations...
  • EJB MDG Technology for Enterprise Java Beans allows the user to model EJB entities and EJB sessions, complete with UML profiles for modeling EJB, EJB patterns and Code Management. (requires Enterprise Architect 4.1 or later)
  • ICONIX AGILE DDT ICONIX Agile Developer - Design-Driven Testing (DDT) streamlines the ICONIX modeling process, providing: Convenient modeling of robustness diagrams Automatic generation of sequence diagram structures from robustness diagrams Transformation of robustness control elements to test diagrams Transformation of sequence diagram elements to test diagrams Transformation of requirement diagrams to test diagrams Transformation between test cases and test classes. (JUnit & NUnit) Built-in model validation rules for ICONIX robustness diagrams (requires Enterprise Architect 7.5 or later)
  • Testing MDG Technology for Testing helps users to rapidly model a wide range of testing procedures including component testing, SUT, Test Cases and more. (requires Enterprise Architect 4.1 or later)
  • Instructions for loading an MDG Technology EXE file: Download and run the .exe file to install the MDG technology. Open Enterprise Architect. Select from the Main Menu Add-Ins | XYZ Technology | Load.
  • Built-in MDG Technologies: Most of the MDG Technologies provided by Sparx Systems are built into Enterprise Architect directly. Depending on your edition of Enterprise Architect, some or all of the following MDG Technologies will be available:
  • Gang of Four Patterns
  • Mind Mapping
  • Web Modeling
  • Data Flow (DFD)
  • Entity-Relationship (ERD)
  • Business Rule Model
  • BPMN™
kuni katsuya

Ontology (information science) - Wikipedia, the free encyclopedia - 0 views

  • an ontology formally represents knowledge as a set of concepts within a domain, and the relationships between those concepts. It can be used to reason about the entities within that domain and may be used to describe the domain
  • n ontology renders shared vocabulary and taxonomy which models a domain with the definition of objects and/or concepts and their properties and relations
  • Common components of ontologies include:
  • ...8 more annotations...
  • Individuals: instances or objects
  • Attributes: aspects, properties, features, characteristics, or parameters
  • Relations: ways in which classes and individuals can be related to one another
  • Function terms:
  • Restrictions: formally stated descriptions of what must be true in order for some assertion to be accepted as input
  • Rules: statements in the form of an if-then (antecedent-consequent) sentence that describe the logical inferences that can be drawn from an assertion in a particular form
  • Axioms: assertions (including rules) in a logical form
  • Events: the changing of attributes or relations
kuni katsuya

Improve your life Through Science and Art: JEE6: Interfaces on Demand with EE6 (CDI & e... - 0 views

  • JEE6: Interfaces on Demand with EE6 (CDI & ejb3.1)
  • JEE6: Interfaces on Demand with EE6 (CDI & ejb3.1)
  • Since Java Platform, Enterprise Edition 6 (Java EE 6),
  • ...9 more annotations...
  • interfaces are no longer required
  • by the container in order to realize common use cases
  • An interface becomes a vehicle for encapsulation or abstraction,
  • as it was originally intended to be:
  • “Interfaces are used to encode similarities which the classes of various types share, but do not necessarily constitute a class relationship. For instance, a human and a parrot can both whistle; however, it would not make sense to represent Humans and Parrots as subclasses of a Whistler class. Rather they would most likely be subclasses of an Animal class (likely with intermediate classes), but both would implement the Whistler interface.” [http://en.wikipedia.org/wiki/Java_interface]
  • Extensive use of interfaces derives from a
  • belief that they might be helpful in the future
  • Premature Extensibility Is the Root of Some Evil
  • The number of artifacts will double and you will have to introduce a configuration facility
kuni katsuya

MySQL Error Number 1005 Can't create table '.mydb#sql-328_45.frm' (errno: 150) | VerySi... - 0 views

  • MySQL Error Number 1005 Can’t create table
  • (errno: 150)
  • SHOW ENGINE INNODB STATUS
  • ...12 more annotations...
  • Known Causes:
  • First Steps:
  • dreaded errno 150:
  • The two key fields type and/or size is not an exact match
  • One of the key field that you are trying to reference does not have an index and/or is not a primary key
  • One or both of your tables is a MyISAM table
  • You have specified a cascade ON DELETE SET NULL, but the relevant key field is set to NOT NULL
  • Make sure that the Charset and Collate options are the same both at the table level as well as individual field level for the key columns
  • You have a default value (ie default=0) on your foreign key column
  • You have a syntax error in your ALTER statement or you have mistyped one of the field names in the relationship
  • The name of your foreign key exceeds the
  • max length of 64 chars
    • kuni katsuya
       
      64 char max? seriously??? in this century?!
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