Table of Contents

Upgrading the database

New releases of Resourcefull.SqlServer can add to the database's schema. This page covers bringing a database up to date, and recording hashes for files stored before the database kept them. Moving from a release before 3.0 has steps of its own; see Upgrading to 3.0.

Upgrading the schema

New releases can add migrations. Before upgrading the package in production:

  1. Check what the release changes in the database, and, from before 3.0, the 3.0 guide, for migrations that need preparation.
  2. Back up the database.
  3. Apply the migrations, with MigrateResourcefullDatabaseAsync or the scripts, during a maintenance window if the upgrade guide says a migration needs one.

To apply the scripts step by step, run the ones under scripts/Migrations/ that the database is missing, oldest first, with sqlcmd -b -I (or SSMS in SQLCMD mode with :on error exit at the top; otherwise SSMS carries on after an error). Each script applies one migration, skips itself when __EFMigrationsHistory already records it, and is safe to run again if it's interrupted. Resourcefull.sql applies all of them in one go.

With the tables in a schema 4.0, the packaged scripts won't work, since they're written for tables in the default schema; generate a script with GenerateResourcefullScript from the upgraded application instead. Like Resourcefull.sql, it applies whatever the database is missing.

Recording hashes for older versions

Every version stored by 3.0 or later records its SHA-256 hash. Versions stored earlier have ContentHash = null until ContentHashBackfill, which UseSqlServer registers, hashes them:

using Resourcefull.SqlServer;

using IServiceScope scope = app.Services.CreateScope();
ContentHashBackfill backfill = scope.ServiceProvider.GetRequiredService<ContentHashBackfill>();
ContentHashBackfillResult result = await backfill.RunAsync(cancellationToken);

logger.LogInformation("Hashed {Count} versions", result.Hashed);
foreach (ContentLengthMismatch mismatch in result.Mismatches)
{
    logger.LogWarning("{Container}/{Name} {Version}: recorded {Recorded} bytes, stored {Stored}",
        mismatch.ContainerName, mismatch.Name, mismatch.VersionId, mismatch.RecordedLength, mismatch.StoredLength);
}
  • It reads each unhashed version's content once, so run it when the load allows. The application can keep running meanwhile.
  • It's resumable. It saves each hash as soon as it's computed, so you can cancel it at any time, and the next run carries on where it stopped. Once every version has a hash, a run reads no content.
  • It reports every length mismatch on every run. Earlier releases recorded the length the caller declared rather than measuring it, so a version's ContentLength can be wrong. The backfill hashes such versions anyway and keeps reporting them until you correct their ContentLength.
Edit this page