IW4M-Admin/SharedLibraryCore/Migrations/20191030000713_EnforceUniqueIndexForEFAliasIPName.cs

using Microsoft.EntityFrameworkCore.Migrations;

namespace SharedLibraryCore.Migrations
{
    public partial class EnforceUniqueIndexForEFAliasIPName : Migration
    {
        protected override void Up(MigrationBuilder migrationBuilder)
        {
            if (migrationBuilder.ActiveProvider == "Microsoft.EntityFrameworkCore.Sqlite")
            {
                migrationBuilder.Sql(@"DELETE FROM EFAlias WHERE AliasId IN (
                                        SELECT AliasId from (
                                        SELECT AliasId, Name, Min(DateAdded), IPAddress FROM EFAlias where (IPAddress, Name) in (SELECT DISTINCT IPAddress, Name FROM EFAlias GROUP BY EFAlias.IPAddress, Name HAVING count(IPAddress) > 1 AND count(Name) > 1)
                                        GROUP BY IPAddress ORDER BY IPAddress))", true);
                migrationBuilder.Sql(@"CREATE UNIQUE INDEX IX_EFAlias_Name_IPAddress ON EFAlias ( IPAddress, Name );", true);
                return;
            }

            else if (migrationBuilder.ActiveProvider == "Pomelo.EntityFrameworkCore.MySql")
            {
                migrationBuilder.Sql(@"CREATE TEMPORARY TABLE DUPLICATE_ALIASES
SELECT
    MIN(`AliasId`) `MIN`,
    MAX(`AliasId`) `MAX`,
    `LinkId`
FROM
    `EFAlias`
WHERE
    (`IPAddress`, `NAME`) IN(
    SELECT DISTINCT
        `IPAddress`,
        `NAME`
    FROM
        `EFAlias`
    GROUP BY
        `EFAlias`.`IPAddress`,
        `NAME`
    HAVING
        COUNT(`IPAddress`) > 1 AND COUNT(`NAME`) > 1
)
GROUP BY
    `IPAddress`
ORDER BY
    `IPAddress`;
SET
    SQL_SAFE_UPDATES = 0;
UPDATE
    `EFClients` AS `Client`
JOIN
    DUPLICATE_ALIASES `Duplicate`
ON
    `Client`.CurrentAliasId = `Duplicate`.`MIN`
SET
    `Client`.CurrentAliasId = `Duplicate`.`MAX`
WHERE
    `Client`.`CurrentAliasId` IN(
    SELECT
        `MIN`
    FROM
        DUPLICATE_ALIASES
);
DELETE
FROM
    `EFAlias`
WHERE
    `AliasId` IN(
    SELECT
        `MIN`
    FROM
        DUPLICATE_ALIASES
);
SET
    SQL_SAFE_UPDATES = 1;
DROP TABLE
    DUPLICATE_ALIASES;");
            }

            else
            {
                migrationBuilder.Sql(@"DELETE 
FROM ""EFAlias"" 
WHERE ""AliasId""
IN
(
    SELECT MIN(""AliasId"") AliasId

    FROM ""EFAlias"" WHERE(""IPAddress"", ""Name"")

     IN
    (
        SELECT DISTINCT ""IPAddress"", ""Name""

        FROM ""EFAlias""

        GROUP BY ""EFAlias"".""IPAddress"", ""Name""

        HAVING COUNT(""IPAddress"") > 1 AND COUNT(""Name"") > 1
    )

    GROUP BY ""IPAddress""

    ORDER BY ""IPAddress""
)", true);
            }

            migrationBuilder.CreateIndex(
                    name: "IX_EFAlias_Name_IPAddress",
                    table: "EFAlias",
                    columns: new[] { "Name", "IPAddress" },
                    unique: true);
        }

        protected override void Down(MigrationBuilder migrationBuilder)
        {
            migrationBuilder.DropIndex(
                name: "IX_EFAlias_Name_IPAddress",
                table: "EFAlias");
        }
    }
}