Oracle provider

src/Simple.Migrations.IntegrationTests/ConnectionStrings.cs

@@ -13,5 +13,6 @@ public static class ConnectionStrings
         public static readonly string MSSQL = @"Server=.;Database=SimpleMigratorTests;Trusted_Connection=True;";
         public static readonly string MySQL = @"Server=localhost;Database=SimpleMigrator;Uid=SimpleMigrator;Pwd=SimpleMigrator;";
         public static readonly string PostgreSQL = @"Server=localhost;Port=5432;Database=SimpleMigrator;User ID=SimpleMigrator;Password=SimpleMigrator";
+        public static readonly string Oracle = @"Data Source=localhost:32769/ORCLPDB1.localdomain;User ID=SimpleMigrator;Password=SimpleMigrator";
     }
 }

src/Simple.Migrations.IntegrationTests/Oracle/OracleStringsProvider.cs

@@ -0,0 +1,11 @@
+namespace Simple.Migrations.IntegrationTests.Oracle
+{
+    public class OracleStringsProvider : IMigrationStringsProvider
+    {
+        public string CreateUsersTableUp => @"CREATE TABLE Users (
+                Id INTEGER NOT NULL PRIMARY KEY,
+                Name VARCHAR2(100) NOT NULL
+            )";
+        public string CreateUsersTableDown => "DROP TABLE Users PURGE";
+    }
+}

src/Simple.Migrations.IntegrationTests/Oracle/OracleTests.cs

@@ -0,0 +1,59 @@
+using System.Data.Common;
+using Npgsql;
+using NUnit.Framework;
+using Oracle.ManagedDataAccess.Client;
+using Simple.Migrations.IntegrationTests.Postgresql;
+using SimpleMigrations;
+using SimpleMigrations.DatabaseProvider;
+
+namespace Simple.Migrations.IntegrationTests.Oracle
+{
+    [TestFixture]
+    public class OracleTests : TestsBase
+    {
+        protected override IDatabaseProvider<DbConnection> CreateDatabaseProvider() => new OracleDatabaseProvider(this.CreateConnection);
+
+        protected override IMigrationStringsProvider MigrationStringsProvider { get; } = new OracleStringsProvider();
+
+        protected override bool SupportConcurrentMigrators => true;
+
+        protected override void Clean()
+        {
+            var connection = this.CreateOraConnection();
+            connection.Open();
+
+            using (var cmd = new OracleCommand(@"
+BEGIN
+    FOR CURTAB IN (SELECT TABLE_NAME FROM USER_TABLES) LOOP
+        BEGIN 
+                EXECUTE IMMEDIATE 'DROP TABLE '||curtab.table_name||' PURGE';
+        EXCEPTION WHEN OTHERS THEN
+            IF (SQLCODE = -942) THEN 
+                NULL;
+            ELSE
+                RAISE;
+            END IF;
+        END;
+    END LOOP;
+
+    BEGIN 
+        EXECUTE IMMEDIATE 'DROP SEQUENCE SEQ_VERSION_TABLE';
+    EXCEPTION WHEN OTHERS THEN
+            IF (SQLCODE = -2289) THEN 
+                NULL;
+            ELSE
+                RAISE;
+            END IF;
+    END;
+END;
+", connection))
+            {
+                cmd.ExecuteNonQuery();
+            }
+        }
+
+        private OracleConnection CreateOraConnection() => new OracleConnection(ConnectionStrings.Oracle);
+
+        protected override DbConnection CreateConnection() => this.CreateOraConnection();
+    }
+}

src/Simple.Migrations.IntegrationTests/Simple.Migrations.IntegrationTests.csproj

@@ -7,12 +7,18 @@
     <GenerateRuntimeConfigurationFiles>true</GenerateRuntimeConfigurationFiles>
   </PropertyGroup>
 
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
+    <DebugType>full</DebugType>
+    <DebugSymbols>true</DebugSymbols>
+  </PropertyGroup>
+
   <ItemGroup>
     <ProjectReference Include="..\Simple.Migrations\Simple.Migrations.csproj" />
   </ItemGroup>
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.0.0-preview-20170106-08" />
+    <PackageReference Include="Oracle.ManagedDataAccess" Version="12.2.1100" />
     <PackageReference Include="System.Reflection.Extensions" Version="4.0.1" />
     <PackageReference Include="NUnit" Version="3.5.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="4.0.0-ci-00457-pr-313" />
@@ -32,4 +38,8 @@
     <Folder Include="Properties\" />
   </ItemGroup>
 
+  <ItemGroup>
+    <Service Include="{82a7f48d-3b50-4b1e-b82e-3ada8210c358}" />
+  </ItemGroup>
+
 </Project>

src/Simple.Migrations/DatabaseProvider/OracleDatabaseProvider.cs

@@ -0,0 +1,121 @@
+using System;
+using System.Data.Common;
+
+namespace SimpleMigrations.DatabaseProvider
+{
+    /// <summary>
+    /// Class which can read from / write to a version table in an PostgreSQL database
+    /// </summary>
+    /// <remarks>
+    /// PostgreSQL supports advisory locks, so these are used to guard against concurrent migrators.
+    /// </remarks>
+    public class OracleDatabaseProvider : DatabaseProviderBaseWithVersionTableLock
+    {
+        /// <summary>
+        /// Name of Oracle Sequence for generating Id in version table
+        /// 
+        /// </summary>
+        public string VersionSequenceName { get; set; } = "SEQ_VERSION_TABLE";
+
+        /// <summary>
+        /// Controls whether or not to try and create the schema if it does not exist.
+        /// </summary>
+        /// <remarks>
+        /// If this is set to false then no schema is created. It is the user's responsibility to create the schema
+        /// (if necessary) with the correct name and permissions before running the <see cref="SimpleMigrator"/>. This may be
+        /// required if the user which Simple.Migrator is running as does not have the correct permissions to check whether the
+        /// schema has been created.
+        /// </remarks>
+        public bool CreateSchema { get; set; } = false;
+
+
+        /// <summary>
+        /// Initialises a new instance of the <see cref="OracleDatabaseProvider"/> class
+        /// </summary>
+        /// <param name="connectionFactory">Connection to use to run migrations. The caller is responsible for closing this.</param>
+        public OracleDatabaseProvider(Func<DbConnection> connectionFactory)
+            : base(connectionFactory)
+        {
+            TableName = "VERSION_INFO";
+        }
+
+
+        /// <summary>
+        /// Returns SQL to create the version table
+        /// </summary>
+        /// <returns>SQL to create the version table</returns>
+        protected override string GetCreateVersionTableSql()
+        {
+            return $@"DECLARE
+    PROCEDURE CREATE_IF_NOT_EXISTS(p_object VARCHAR2, p_sql VARCHAR2)
+    IS
+    c_object user_objects.object_name%type;
+    BEGIN
+        BEGIN
+          SELECT object_name INTO c_object FROM user_objects WHERE object_name=p_object;
+          EXCEPTION WHEN no_data_found then          
+          BEGIN 
+              EXECUTE IMMEDIATE p_sql;        
+           EXCEPTION WHEN OTHERS THEN 
+            IF (SQLCODE = -955) THEN 
+                NULL;
+             ELSE
+                RAISE;
+             END IF;   
+        END;
+    END;
+    END;
+BEGIN        
+       CREATE_IF_NOT_EXISTS('{this.VersionSequenceName}','CREATE SEQUENCE {this.VersionSequenceName} START WITH 1 NOCACHE');
+
+       CREATE_IF_NOT_EXISTS('{this.TableName}','CREATE TABLE {this.TableName}(
+        ID INTEGER PRIMARY KEY,
+        VERSION INTEGER NOT NULL,
+        APPLIED_ON timestamp with time zone,
+        DESCRIPTION varchar2(4000) NOT NULL
+        )');                  
+END;
+";
+        }
+
+
+
+
+        /// <summary>
+        /// Returns SQL to fetch the current version from the version table
+        /// </summary>
+        /// <returns>SQL to fetch the current version from the version table</returns>
+        protected override string GetCurrentVersionSql()
+        {
+            return $@"SELECT VERSION FROM (SELECT VERSION FROM {this.TableName} ORDER BY ID DESC) WHERE ROWNUM=1";
+        }
+
+        /// <summary>
+        /// Returns SQL to update the current version in the version table
+        /// </summary>
+        /// <returns>SQL to update the current version in the version table</returns>
+        protected override string GetSetVersionSql()
+        {
+            //RETURNING VERSION INTO :OldVersion - required use of bind variable to aviod oracle error
+            return $@"INSERT INTO {this.TableName} (ID, VERSION, APPLIED_ON, DESCRIPTION) VALUES ({this.VersionSequenceName}.NEXTVAL, :Version, CURRENT_TIMESTAMP, :Description) RETURNING VERSION INTO :OldVersion";
+        }
+
+        protected override void AcquireVersionTableLock()
+        {
+            VersionTableLockTransaction = this.VersionTableConnection.BeginTransaction();
+            using (var cmd = this.VersionTableConnection.CreateCommand())
+            {
+                cmd.Transaction = VersionTableLockTransaction;
+                cmd.CommandText = $"LOCK TABLE {TableName} IN EXCLUSIVE MODE";
+                cmd.ExecuteNonQuery();
+            }
+        }
+
+        protected override void ReleaseVersionTableLock()
+        {
+            VersionTableLockTransaction.Commit();
+            VersionTableLockTransaction.Dispose();
+            VersionTableLockTransaction = null;
+        }
+    }
+}