BasicCellRelation.cs source code in C# .NET

                        Code:
                         / Dotnetfx_Win7_3.5.1 / Dotnetfx_Win7_3.5.1 / 3.5.1 / DEVDIV / depot / DevDiv / releases / Orcas / NetFXw7 / ndp / fx / src / DataEntity / System / Data / Map / ViewGeneration / Validation / BasicCellRelation.cs / 1 / BasicCellRelation.cs
                        
                        
                            //---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.Bharani1729
// 
// 
// @owner [....]
// @backupOwner [....] 
//--------------------------------------------------------------------- 

using System.Collections.Generic; 
using System.Data.Mapping.ViewGeneration.Structures;
using System.Text;
using System.Diagnostics;
using System.Data.Common.Utils; 
using System.Data.Metadata.Edm;
 
namespace System.Data.Mapping.ViewGeneration.Validation { 

    using BasicSchemaConstraints = SchemaConstraints; 

    // This class represents a relation signature that lists all scalar
    // slots for the join tree in cell query (before projection)
    internal class BasicCellRelation : CellRelation { 

        #region Constructor 
        // effects: Creates a basic cell relation for query 
        internal BasicCellRelation(CellQuery cellQuery, ViewCellRelation viewCellRelation,
                                   IEnumerable slots) : base(viewCellRelation.CellNumber) { 
            m_cellQuery = cellQuery;
            m_slots = new List(slots);
            Debug.Assert(m_slots.Count > 0, "Cell relation with not even an exent?");
            m_viewCellRelation = viewCellRelation; 
        }
        #endregion 
 
        #region Fields
        private CellQuery m_cellQuery; 
        private List m_slots;
        private ViewCellRelation m_viewCellRelation; // The viewcellrelation
                                                     // corresponding to this basiccellrelation
        #endregion 

        #region Properties 
        internal ViewCellRelation ViewCellRelation { 
            get { return m_viewCellRelation;}
        } 
        #endregion

        #region Key Constraints Methods
        // effects: Modifies constraints to contain the key constraints that 
        // are present in this relation
        internal void PopulateKeyConstraints(BasicSchemaConstraints constraints, MetadataWorkspace workspace) { 
            Debug.Assert(this == m_cellQuery.BasicCellRelation, "Cellquery does not point to the correct BasicCellRelation?"); 
            Debug.Assert(m_cellQuery.Extent is EntitySet || m_cellQuery.Extent is AssociationSet,
                         "Top level extents handled is currently entityset or association set"); 
            if (m_cellQuery.Extent is EntitySet) {
                PopulateKeyConstraintsForEntitySet(constraints, workspace);
            } else {
                PopulateKeyConstraintsForRelationshipSet(constraints, workspace); 
            }
        } 
 
        // requires: this to correspond to a cell relation for an entityset (m_cellQuery.Extent)
        // effects: Adds any key constraints present in this to constraints 
        private void PopulateKeyConstraintsForEntitySet(BasicSchemaConstraints constraints, MetadataWorkspace workspace) {
            MemberPath prefix = new MemberPath(m_cellQuery.Extent, workspace);
            EntityType entityType = (EntityType) m_cellQuery.Extent.ElementType;
 
            // Get all the keys for the entity type and create the key constraints
            List keys = ExtentKey.GetKeysForEntityType(prefix, entityType); 
            AddKeyConstraints(keys, constraints); 
        }
 
        // requires: this to correspond to a cell relation for an association set (m_cellQuery.Extent)
        // effects: Adds any key constraints present in this relation in
        // constraints
        private void PopulateKeyConstraintsForRelationshipSet(BasicSchemaConstraints constraints, MetadataWorkspace workspace) { 
            AssociationSet relationshipSet = m_cellQuery.Extent as AssociationSet;
            // Gather all members of all keys 
            // CHANGE_[....]_FEATURE_KEYS: assume that an Entity has exactly one key. Otherwise we 
            // have to take a cross-product of all keys
 
            // Keep track of all the key members for the association in a set
            // so that if no end corresponds to a key, we use all the members
            // to form the key
            Set associationKeyMembers = new Set(MemberPath.EqualityComparer); 
            bool hasAnEndThatFormsKey = false;
 
            // Determine the keys of each end. If the end forms a key, add it 
            // as a key to the set
 
            foreach (AssociationSetEnd end in relationshipSet.AssociationSetEnds) {
                AssociationEndMember endMember = end.CorrespondingAssociationEndMember;

                MemberPath prefix = new MemberPath(relationshipSet, endMember, workspace); 
                List keys = ExtentKey.GetKeysForEntityType(prefix, end.EntitySet.ElementType);
                Debug.Assert(keys.Count > 0, "No keys for entity?"); 
                Debug.Assert(keys.Count == 1, "Currently, we only support primary keys"); 

                if (MetadataHelper.DoesEndFormKey(relationshipSet, endMember)) { 
                    // This end has is a key end
                    AddKeyConstraints(keys, constraints);
                    hasAnEndThatFormsKey = true;
                } 
                // Add the members of the (only) key to associationKey
                associationKeyMembers.AddRange(keys[0].KeyFields); 
            } 
            // If an end forms a key then that key implies the full key
            if (false == hasAnEndThatFormsKey) { 
                // No end is a key -- take all the end members and make a key
                // based on that
                ExtentKey key = new ExtentKey(associationKeyMembers);
                ExtentKey[] keys = new ExtentKey[] { key }; 
                AddKeyConstraints(keys, constraints);
            } 
        } 

        // effects: Given keys for this relation, adds one key constraint for 
        // each key present in keys
        private void AddKeyConstraints(IEnumerable keys, BasicSchemaConstraints constraints) {
            foreach (ExtentKey key in keys) {
                // If the key is being projected, only then do we add the key constraint 

                List keySlots = JoinTreeSlot.GetSlots(m_slots, key.KeyFields); 
                if (keySlots != null) { 
                    BasicKeyConstraint keyConstraint = new BasicKeyConstraint(this, keySlots);
                    constraints.Add(keyConstraint); 
                }
            }
        }
        #endregion 

        #region Comparer/String Methods 
        protected override int GetHash() { 
            // Note: Using CLR-Hashcode
            return m_cellQuery.GetHashCode(); 
            // We need not hash the slots, etc - cellQuery should give us enough
            // differentiation and land the relation into the same bucket
        }
 
        internal override void ToCompactString(StringBuilder builder) {
            builder.Append("BasicRel: "); 
            // Just print the extent name from slot 0 
            StringUtil.FormatStringBuilder(builder, "{0}", m_slots[0]);
        } 
        #endregion
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.Bharani1729
// 
// 
// @owner [....]
// @backupOwner [....] 
//--------------------------------------------------------------------- 

using System.Collections.Generic; 
using System.Data.Mapping.ViewGeneration.Structures;
using System.Text;
using System.Diagnostics;
using System.Data.Common.Utils; 
using System.Data.Metadata.Edm;
 
namespace System.Data.Mapping.ViewGeneration.Validation { 

    using BasicSchemaConstraints = SchemaConstraints; 

    // This class represents a relation signature that lists all scalar
    // slots for the join tree in cell query (before projection)
    internal class BasicCellRelation : CellRelation { 

        #region Constructor 
        // effects: Creates a basic cell relation for query 
        internal BasicCellRelation(CellQuery cellQuery, ViewCellRelation viewCellRelation,
                                   IEnumerable slots) : base(viewCellRelation.CellNumber) { 
            m_cellQuery = cellQuery;
            m_slots = new List(slots);
            Debug.Assert(m_slots.Count > 0, "Cell relation with not even an exent?");
            m_viewCellRelation = viewCellRelation; 
        }
        #endregion 
 
        #region Fields
        private CellQuery m_cellQuery; 
        private List m_slots;
        private ViewCellRelation m_viewCellRelation; // The viewcellrelation
                                                     // corresponding to this basiccellrelation
        #endregion 

        #region Properties 
        internal ViewCellRelation ViewCellRelation { 
            get { return m_viewCellRelation;}
        } 
        #endregion

        #region Key Constraints Methods
        // effects: Modifies constraints to contain the key constraints that 
        // are present in this relation
        internal void PopulateKeyConstraints(BasicSchemaConstraints constraints, MetadataWorkspace workspace) { 
            Debug.Assert(this == m_cellQuery.BasicCellRelation, "Cellquery does not point to the correct BasicCellRelation?"); 
            Debug.Assert(m_cellQuery.Extent is EntitySet || m_cellQuery.Extent is AssociationSet,
                         "Top level extents handled is currently entityset or association set"); 
            if (m_cellQuery.Extent is EntitySet) {
                PopulateKeyConstraintsForEntitySet(constraints, workspace);
            } else {
                PopulateKeyConstraintsForRelationshipSet(constraints, workspace); 
            }
        } 
 
        // requires: this to correspond to a cell relation for an entityset (m_cellQuery.Extent)
        // effects: Adds any key constraints present in this to constraints 
        private void PopulateKeyConstraintsForEntitySet(BasicSchemaConstraints constraints, MetadataWorkspace workspace) {
            MemberPath prefix = new MemberPath(m_cellQuery.Extent, workspace);
            EntityType entityType = (EntityType) m_cellQuery.Extent.ElementType;
 
            // Get all the keys for the entity type and create the key constraints
            List keys = ExtentKey.GetKeysForEntityType(prefix, entityType); 
            AddKeyConstraints(keys, constraints); 
        }
 
        // requires: this to correspond to a cell relation for an association set (m_cellQuery.Extent)
        // effects: Adds any key constraints present in this relation in
        // constraints
        private void PopulateKeyConstraintsForRelationshipSet(BasicSchemaConstraints constraints, MetadataWorkspace workspace) { 
            AssociationSet relationshipSet = m_cellQuery.Extent as AssociationSet;
            // Gather all members of all keys 
            // CHANGE_[....]_FEATURE_KEYS: assume that an Entity has exactly one key. Otherwise we 
            // have to take a cross-product of all keys
 
            // Keep track of all the key members for the association in a set
            // so that if no end corresponds to a key, we use all the members
            // to form the key
            Set associationKeyMembers = new Set(MemberPath.EqualityComparer); 
            bool hasAnEndThatFormsKey = false;
 
            // Determine the keys of each end. If the end forms a key, add it 
            // as a key to the set
 
            foreach (AssociationSetEnd end in relationshipSet.AssociationSetEnds) {
                AssociationEndMember endMember = end.CorrespondingAssociationEndMember;

                MemberPath prefix = new MemberPath(relationshipSet, endMember, workspace); 
                List keys = ExtentKey.GetKeysForEntityType(prefix, end.EntitySet.ElementType);
                Debug.Assert(keys.Count > 0, "No keys for entity?"); 
                Debug.Assert(keys.Count == 1, "Currently, we only support primary keys"); 

                if (MetadataHelper.DoesEndFormKey(relationshipSet, endMember)) { 
                    // This end has is a key end
                    AddKeyConstraints(keys, constraints);
                    hasAnEndThatFormsKey = true;
                } 
                // Add the members of the (only) key to associationKey
                associationKeyMembers.AddRange(keys[0].KeyFields); 
            } 
            // If an end forms a key then that key implies the full key
            if (false == hasAnEndThatFormsKey) { 
                // No end is a key -- take all the end members and make a key
                // based on that
                ExtentKey key = new ExtentKey(associationKeyMembers);
                ExtentKey[] keys = new ExtentKey[] { key }; 
                AddKeyConstraints(keys, constraints);
            } 
        } 

        // effects: Given keys for this relation, adds one key constraint for 
        // each key present in keys
        private void AddKeyConstraints(IEnumerable keys, BasicSchemaConstraints constraints) {
            foreach (ExtentKey key in keys) {
                // If the key is being projected, only then do we add the key constraint 

                List keySlots = JoinTreeSlot.GetSlots(m_slots, key.KeyFields); 
                if (keySlots != null) { 
                    BasicKeyConstraint keyConstraint = new BasicKeyConstraint(this, keySlots);
                    constraints.Add(keyConstraint); 
                }
            }
        }
        #endregion 

        #region Comparer/String Methods 
        protected override int GetHash() { 
            // Note: Using CLR-Hashcode
            return m_cellQuery.GetHashCode(); 
            // We need not hash the slots, etc - cellQuery should give us enough
            // differentiation and land the relation into the same bucket
        }
 
        internal override void ToCompactString(StringBuilder builder) {
            builder.Append("BasicRel: "); 
            // Just print the extent name from slot 0 
            StringUtil.FormatStringBuilder(builder, "{0}", m_slots[0]);
        } 
        #endregion
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
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BasicCellRelation.cs source code in C# .NET

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