dotnet/efcore · error · InvalidOperationException

Table name must be specified to configure a table-specific…

Error message

Table name must be specified to configure a table-specific property mapping.

What it means

OwnedNavigationTableBuilder.GetStoreObjectIdentifier() returns the builder's StoreObject; if it is null it throws MappingFragmentMissingName. Table-specific property configuration (Property(...)) needs a concrete named table to bind a column override to, so calling it on a builder that has no table name is invalid.

Solutions

Specify a table name first: .ToTable("Address") (or .ToTable("Address", schema)) so the builder carries a StoreObjectIdentifier.
If you do not need table-specific overrides, use the non-table-specific property configuration on the owned navigation builder directly.
Confirm the OwnedNavigationTableBuilder you are using was produced from a named ToTable call.

Example fix

// before — table builder with no name
modelBuilder.Entity<Customer>()
    .OwnsOne(c => c.Address, a =>
    {
        a.ToTable(tb => tb.Property("Line1").HasColumnName("AddrLine1")); // no table name -> [454]
    });

// after — give the table a name
modelBuilder.Entity<Customer>()
    .OwnsOne(c => c.Address, a =>
    {
        a.ToTable("CustomerAddress", tb => tb.Property(a => a.Line1).HasColumnName("AddrLine1"));
    });

Defensive patterns

Strategy: validation

Validate before calling

// Ensure a table name is supplied before using table-specific property config.
if (string.IsNullOrEmpty(tableName))
    throw new InvalidOperationException("A table name is required for table-specific property mapping.");

Prevention

Always call .ToTable(name, ...) before configuring table-specific columns.
If you do not need table-specific overrides, configure the property on the entity builder directly.
Review builder chaining to confirm the OwnedNavigationTableBuilder came from a named ToTable.

When it happens

Trigger: Invoking .Property("X") (or another table-specific method) on an OwnedNavigationTableBuilder whose StoreObject is null — e.g. the builder was obtained without a named table (a default/empty table builder) and you tried to configure a column mapping on it.

Common situations: Calling table-specific property config off an OwnedNavigationTableBuilder created for a default mapping; misusing a builder returned before .ToTable(name) was applied; chaining APIs incorrectly.

Related errors

AI-assisted analysis of dotnet/efcore@3a2006ef56 (2026-08-11). Data as JSON: /api/errors/0b376604087c3ee3. Report an issue: GitHub.

Appendix: source

Thrown at src/EFCore.Relational/Metadata/Builders/OwnedNavigationTableBuilder.cs:164

    /// <summary>
    ///     Maps the property to a column on the current table and returns an object that can be used
    ///     to provide table-specific configuration if the property is mapped to more than one table.
    /// </summary>
    /// <typeparam name="TProperty">The type of the property to be configured.</typeparam>
    /// <param name="propertyName">The name of the property to be configured.</param>
    /// <returns>An object that can be used to configure the property.</returns>
    public virtual ColumnBuilder<TProperty> Property<TProperty>(string propertyName)
        => new(GetStoreObjectIdentifier(), OwnedNavigationBuilder.Property<TProperty>(propertyName));

    /// <summary>
    ///     This is an internal API that supports the Entity Framework Core infrastructure and not subject to
    ///     the same compatibility standards as public APIs. It may be changed or removed without notice in
    ///     any release. You should only use it directly in your code with extreme caution and knowing that
    ///     doing so can result in application failures when updating to a new Entity Framework Core release.
    /// </summary>
    [EntityFrameworkInternal]
    protected virtual StoreObjectIdentifier GetStoreObjectIdentifier()
        => StoreObject ?? throw new InvalidOperationException(RelationalStrings.MappingFragmentMissingName);

    OwnedNavigationBuilder IInfrastructure<OwnedNavigationBuilder>.Instance
        => OwnedNavigationBuilder;

    #region Hidden System.Object members

    /// <summary>
    ///     Returns a string that represents the current object.
    /// </summary>
    /// <returns>A string that represents the current object.</returns>
    [EditorBrowsable(EditorBrowsableState.Never)]
    public override string? ToString()
        => base.ToString();

    /// <summary>
    ///     Determines whether the specified object is equal to the current object.
    /// </summary>
    /// <param name="obj">The object to compare with the current object.</param>

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