Add functions to migrate indexes and constraints

Author: Hadi Fadlallah

SQLToNeo4j/Edge.cs

@@ -24,6 +24,7 @@ public Edge(string id, string label, string from, string fromID, string to, stri
                 Properties = properties;
             else
                 Properties = new Dictionary<string, object>();
+
         }
 
     }

SQLToNeo4j/Neo4jWriter.cs

@@ -21,9 +21,9 @@ public void ImportNodes(List<Node> nodes)
                 string cypher =
                 "(" + nd.Label + "_" + nd.ID.ToString() + ":" + nd.Label + " $prop)";
                 client.Cypher.Create(cypher).WithParam("prop", nd.Properties).ExecuteWithoutResultsAsync().Wait(); ;
+            
             }        
         }
-
         public void ImportEdges(List<Edge> edges)
         {
             foreach (Edge edg in edges)
@@ -39,10 +39,24 @@ public void ImportEdges(List<Edge> edges)
                     .Where(edg.FromNode.ToLower() + "1.node_id = $id1")
                     .AndWhere(edg.ToNode.ToLower() + "2.node_id = $id2")
                     .Create(cypher)
-                    .WithParams(param).ExecuteWithoutResultsAsync().Wait(); ;
+                    .WithParams(param).ExecuteWithoutResultsAsync().Wait(); 
             }
         }
-
+        public void ImportIndexes(List<string> indexes)
+        {
+            foreach(string cmd in indexes)
+                client.Cypher.Create(cmd).ExecuteWithoutResultsAsync().Wait();
+         }
+        public void ImportFullTextIndexes(List<string> ftindexes)
+        {
+            foreach (string cmd in ftindexes)
+                client.Cypher.Call(cmd).ExecuteWithoutResultsAsync().Wait();
+        }
+        public void ImportConstraints(List<string> constraints)
+        {
+            foreach (string cmd in constraints)
+                client.Cypher.Create(cmd).ExecuteWithoutResultsAsync().Wait();
+        }
         public void Dispose()
         {
             client.Dispose();

SQLToNeo4j/SQLCommands.cs

@@ -0,0 +1,39 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace SQLToNeo4j
+{
+    public static class SQLcommands
+    {
+        public static string GetIndexes = "SELECT 'INDEX ' + ind.name + ' FOR (t:' + t.name +') ON (' + STRING_AGG('t.' + Col.name,',') + ')'" +
+                                " FROM sys.indexes ind INNER JOIN sys.index_columns ic ON  ind.object_id = ic.object_id and ind.index_id = ic.index_id INNER JOIN sys.columns col ON ic.object_id = col.object_id and ic.column_id = col.column_id INNER JOIN sys.tables t ON ind.object_id = t.object_id" +
+                                " WHERE ind.type = 2 and (t.is_node = 1 or t.is_edge = 1) and col.name not like 'graph_id_%' and t.name <> 'sysdiagrams'" +
+                                " GROUP BY  ind.name,  t.name";
+        public static string GetFullTextIndexes = "SELECT 'db.index.fulltext.' + case t.is_node when 1 then 'createNodeIndex(\"N_' else 'createRelationshipIndex(\"Rel_' end  + cat.name + '\", [' + STRING_AGG('\"' + t.name + '\"',', ') + '], [' + STRING_AGG('\"' + col.name + '\"',', ') + '])' " +
+                                " FROM sys.fulltext_catalogs cat INNER JOIN sys.fulltext_indexes ind ON cat.fulltext_catalog_id = ind.fulltext_catalog_id INNER JOIN sys.fulltext_index_columns ic ON  ind.object_id = ic.object_id " +
+                                " INNER JOIN sys.columns col ON ic.object_id = col.object_id and ic.column_id = col.column_id INNER JOIN sys.tables t ON ind.object_id = t.object_id " +
+                                " WHERE (t.is_node = 1 or t.is_edge = 1) and col.name not like 'graph_id_%' and t.name <> 'sysdiagrams' " +
+                                " GROUP BY t.is_node, cat.name";
+        public static string GetUniqueConstraints = "SELECT 'CONSTRAINT UC_' + ind.name + ' ON (n:' + t.name + ') ASSERT n.' + col.name + ' IS UNIQUE' " +
+                                " FROM sys.indexes ind INNER JOIN  sys.index_columns ic ON  ind.object_id = ic.object_id and ind.index_id = ic.index_id " +
+                                " INNER JOIN sys.columns col ON ic.object_id = col.object_id and ic.column_id = col.column_id " +
+                                " INNER JOIN sys.tables t ON ind.object_id = t.object_id " +
+                                " WHERE ind.type = 2 	and (t.is_node = 1 or t.is_edge = 1) and col.name not like 'graph_id_%' and t.name <> 'sysdiagrams' " +
+                                "	and (ind.is_unique = 1 or ind.is_unique_constraint = 1) " +
+                                " GROUP BY ind.name,t.name,col.name" +
+                                " HAVING COUNT(*) = 1";
+        public static string GetExistenceConstraints = "select CASE WHEN t.is_node = 1 then 'CONSTRAINT ' + t.name + '_' + col.name + '_exist ON (n:' + t.name + ') ASSERT EXISTS (n.' + col.name + ')' ELSE 'CONSTRAINT ' + t.name + '_' + col.name + '_exist ON ()-\"[\"R:' + t.name + '\"]\"-() ASSERT EXISTS (R.' + col.name + ')' END " +
+                                " FROM sys.columns col INNER JOIN  sys.tables t ON col.object_id = t.object_id " +
+                                " where col.is_nullable = 0 and col.graph_type IS NULL and (t.is_edge = 1 or t.is_node = 1) " +
+                                "	and not exists (select * from sys.index_columns ic inner join sys.indexes ind on ic.index_id = ind.index_id and ind.object_id = ic.object_id " +
+                                "		where ind.is_primary_key = 1 and ic.column_id = col.column_id and t.object_id = ind.object_id and t.is_node = 1)";
+        public static string GetNodeKeyConstraints = "select 'CONSTRAINT NKC_' + t.name + ' ON (n:' + t.name + ') ASSERT (' + STRING_AGG('n.' + col.name,',') + ') IS NODE KEY' " +
+                                " FROM sys.indexes ind  INNER JOIN sys.index_columns ic ON ind.object_id = ic.object_id and ind.index_id = ic.index_id INNER JOIN sys.tables t ON ind.object_id = t.object_id " +
+                                " INNER JOIN sys.columns col ON ic.object_id = col.object_id and ic.column_id = col.column_id " +
+                                " where  graph_type IS NULL -- Ignore graph system columns and t.is_node = 1 and ind.is_primary_key = 1 " +
+                                " GROUP BY t.name";
+
+
+    }
+}

SQLToNeo4j/SQLReader.cs

@@ -10,11 +10,22 @@ public class SQLReader : IDisposable
     {
         public List<Node> Nodes { get; set; }
         public List<Edge> Edges { get; set; }
+        public List<string> Indexes { get; set; }
+        public List<string> FullTextIndexes { get; set; }
+        public List<string> UniqueConstraints { get; set; }
+        public List<string> ExistenceConstraints { get; set; }
+        public List<string> NodeKeyConstraints { get; set; }
+
         public string ConnectionString { get; set; }
 
         public SQLReader(string connection)
         {
             ConnectionString = connection;
+            Indexes = new List<string>();
+            FullTextIndexes = new List<string>();
+            UniqueConstraints = new List<string>();
+            ExistenceConstraints = new List<string>();
+            NodeKeyConstraints = new List<string>();
         }
         public void GetNodes()
         {
@@ -153,7 +164,106 @@ public void GetEdges()
             }
 
         }
+        public void GetIndexes()
+        {
+            //initialize connection
+            using (SqlConnection sqlcon = new SqlConnection(ConnectionString))
+            {
+                sqlcon.Open();
+                //retrieving Indexes
+
+                using (SqlCommand sqlIndexes = new SqlCommand(SQLcommands.GetIndexes, sqlcon))
+                {
+                    SqlDataReader indexreader;
+                    indexreader = sqlIndexes.ExecuteReader();
+
+                    //get index create statements
+                    while (indexreader.Read())
+                        Indexes.Add(indexreader[0].ToString());
+                        
+                }
+            }
+        }
+        public void GetFullTextIndexes()
+        {
+            //initialize connection
+            using (SqlConnection sqlcon = new SqlConnection(ConnectionString))
+            {
+                sqlcon.Open();
+                //retrieving Indexes
+
+                using (SqlCommand sqlFullTextIndexes = new SqlCommand(SQLcommands.GetFullTextIndexes, sqlcon))
+                {
+                    SqlDataReader indexreader;
+                    indexreader = sqlFullTextIndexes.ExecuteReader();
+
+                    //get index create statements
+                    while (indexreader.Read())
+                        FullTextIndexes.Add(indexreader[0].ToString());
+
+                }
+            }
+        }
+        public void GetUniqueConstraints()
+        {
+            //initialize connection
+            using (SqlConnection sqlcon = new SqlConnection(ConnectionString))
+            {
+                sqlcon.Open();
+                //retrieving Indexes
 
+                using (SqlCommand sqlUniqueConstraints = new SqlCommand(SQLcommands.GetUniqueConstraints, sqlcon))
+                {
+                    SqlDataReader uqcreader;
+                    uqcreader = sqlUniqueConstraints.ExecuteReader();
+
+                    //get index create statements
+                    while (uqcreader.Read())
+                        UniqueConstraints.Add(uqcreader[0].ToString());
+
+                }
+            }
+        }
+        public void GetExistenceConstraints()
+        {
+            //initialize connection
+            using (SqlConnection sqlcon = new SqlConnection(ConnectionString))
+            {
+                sqlcon.Open();
+                //retrieving Indexes
+
+                using (SqlCommand sqlExistenceConstraints = new SqlCommand(SQLcommands.GetExistenceConstraints, sqlcon))
+                {
+                    SqlDataReader excreader;
+                    excreader = sqlExistenceConstraints.ExecuteReader();
+
+                    //get index create statements
+                    while (excreader.Read())
+                        ExistenceConstraints.Add(excreader[0].ToString());
+
+                }
+            }
+        }
+        public void GetNodeKeyConstraints()
+        {
+            //initialize connection
+            using (SqlConnection sqlcon = new SqlConnection(ConnectionString))
+            {
+                sqlcon.Open();
+                //retrieving Indexes
+
+                using (SqlCommand sqlNodeKeyConstraints = new SqlCommand(SQLcommands.GetNodeKeyConstraints, sqlcon))
+                {
+                    SqlDataReader nkcreader;
+                    nkcreader = sqlNodeKeyConstraints.ExecuteReader();
+
+                    //get index create statements
+                    while (nkcreader.Read())
+                        NodeKeyConstraints.Add(nkcreader[0].ToString());
+
+                }
+            }
+        }
         public void Dispose()
         {
             Nodes = null;

SQLToNeo4jDemo/Program.cs

@@ -6,15 +6,25 @@ class Program
     {
         static void Main(string[] args)
         {
-            using (SQLReader reader = new SQLReader("Server=<machine name>\\<instance name>;Database=GraphPL;Trusted_Connection=yes;"))
+            using (SQLReader reader = new SQLReader("Server=DESKTOP-KCL006K\\DATASERVER;Database=GraphPL;Trusted_Connection=yes;"))
             {
                 reader.GetNodes();
                 reader.GetEdges();
+                reader.GetIndexes();
+                reader.GetFullTextIndexes();
+                reader.GetUniqueConstraints();
+                //reader.GetExistenceConstraints(); -- available only in enterprise edition
+                //reader.GetNodeKeyConstraints(); -- available only in enterprise edition
 
-                using (Neo4jWriter importer = new Neo4jWriter(new Uri("http://<user>:<password>@localhost:7474")))
+                using (Neo4jWriter importer = new Neo4jWriter(new Uri("http://neo4j:123@localhost:7474")))
                 {
                     importer.ImportNodes(reader.Nodes);
                     importer.ImportEdges(reader.Edges);
+                    importer.ImportIndexes(reader.Indexes);
+                    importer.ImportFullTextIndexes(reader.FullTextIndexes);
+                    importer.ImportConstraints(reader.UniqueConstraints);
+                    //importer.ImportConstraints(reader.ExistenceConstraints); -- available only in enterprise edition
+                    //importer.ImportConstraints(reader.NodeKeyConstraints); -- available only in enterprise edition
                 }
             }
         }