From 5d41f5c42bfbb417e422cfb0b523d3cca9c4da49 Mon Sep 17 00:00:00 2001
From: "F.D.Castel" <fdcastel@gmail.com>
Date: Mon, 23 Mar 2026 01:38:57 -0300
Subject: [PATCH] GetIndexesQuery: Exclude expression indexes at the database
 level. Fix #1188.

---
 .../Scaffolding/ScaffoldingTests.cs           | 48 +++++++++++++++++++
 .../Internal/FbDatabaseModelFactory.cs        |  9 +++-
 2 files changed, 56 insertions(+), 1 deletion(-)

diff --git a/src/FirebirdSql.EntityFrameworkCore.Firebird.Tests/Scaffolding/ScaffoldingTests.cs b/src/FirebirdSql.EntityFrameworkCore.Firebird.Tests/Scaffolding/ScaffoldingTests.cs
index 18e903462..4b33cb2eb 100644
--- a/src/FirebirdSql.EntityFrameworkCore.Firebird.Tests/Scaffolding/ScaffoldingTests.cs
+++ b/src/FirebirdSql.EntityFrameworkCore.Firebird.Tests/Scaffolding/ScaffoldingTests.cs
@@ -107,6 +107,54 @@ public async Task ReadsCorrectFieldType(string dataType)
 		Assert.That(column.StoreType, Is.EqualTo(dataType));
 	}
 
+	[Test]
+	public async Task ExpressionIndexDoesNotBreakScaffolding()
+	{
+		var tableName = "TEST_EXPR_IDX";
+
+		using var commandTable = Connection.CreateCommand();
+		commandTable.CommandText = $"recreate table {tableName} (ID INTEGER NOT NULL, DATA VARCHAR(100))";
+		await commandTable.ExecuteNonQueryAsync();
+
+		using var commandIndex = Connection.CreateCommand();
+		commandIndex.CommandText = $"create index IDX_EXPR on {tableName} computed by (upper(DATA))";
+		await commandIndex.ExecuteNonQueryAsync();
+
+		var modelFactory = GetModelFactory();
+		var model = modelFactory.Create(Connection.ConnectionString, new DatabaseModelFactoryOptions(new string[] { tableName }));
+		var table = model.Tables.Single(x => x.Name == tableName);
+
+		Assert.That(table.Indexes, Has.None.Matches<Microsoft.EntityFrameworkCore.Scaffolding.Metadata.DatabaseIndex>(x => x.Name == "IDX_EXPR"));
+	}
+
+	[Test]
+	public async Task RegularIndexScaffoldedAlongsideExpressionIndex()
+	{
+		var tableName = "TEST_MIX_IDX";
+
+		using var commandTable = Connection.CreateCommand();
+		commandTable.CommandText = $"recreate table {tableName} (ID INTEGER NOT NULL, DATA VARCHAR(100))";
+		await commandTable.ExecuteNonQueryAsync();
+
+		using var commandRegularIndex = Connection.CreateCommand();
+		commandRegularIndex.CommandText = $"create index IDX_REGULAR on {tableName} (DATA)";
+		await commandRegularIndex.ExecuteNonQueryAsync();
+
+		using var commandExprIndex = Connection.CreateCommand();
+		commandExprIndex.CommandText = $"create index IDX_EXPR_MIX on {tableName} computed by (upper(DATA))";
+		await commandExprIndex.ExecuteNonQueryAsync();
+
+		var modelFactory = GetModelFactory();
+		var model = modelFactory.Create(Connection.ConnectionString, new DatabaseModelFactoryOptions(new string[] { tableName }));
+		var table = model.Tables.Single(x => x.Name == tableName);
+
+		Assert.Multiple(() =>
+		{
+			Assert.That(table.Indexes, Has.Some.Matches<Microsoft.EntityFrameworkCore.Scaffolding.Metadata.DatabaseIndex>(x => x.Name == "IDX_REGULAR"));
+			Assert.That(table.Indexes, Has.None.Matches<Microsoft.EntityFrameworkCore.Scaffolding.Metadata.DatabaseIndex>(x => x.Name == "IDX_EXPR_MIX"));
+		});
+	}
+
 	static IDatabaseModelFactory GetModelFactory()
 	{
 		return new FbDatabaseModelFactory();
diff --git a/src/FirebirdSql.EntityFrameworkCore.Firebird/Scaffolding/Internal/FbDatabaseModelFactory.cs b/src/FirebirdSql.EntityFrameworkCore.Firebird/Scaffolding/Internal/FbDatabaseModelFactory.cs
index a636e2cb5..d99193722 100644
--- a/src/FirebirdSql.EntityFrameworkCore.Firebird/Scaffolding/Internal/FbDatabaseModelFactory.cs
+++ b/src/FirebirdSql.EntityFrameworkCore.Firebird/Scaffolding/Internal/FbDatabaseModelFactory.cs
@@ -319,6 +319,7 @@ private void GetPrimaryKeys(DbConnection connection, IReadOnlyList<DatabaseTable
                LEFT JOIN rdb$relation_constraints rc on rc.rdb$index_name = I.rdb$index_name and rc.rdb$constraint_type = null
               WHERE
                trim(i.rdb$relation_name) = '{0}'
+               AND i.RDB$EXPRESSION_SOURCE IS NULL
               GROUP BY
                INDEX_NAME, IS_UNIQUE, IS_DESC ;";
 
@@ -337,6 +338,12 @@ private void GetIndexes(DbConnection connection, IReadOnlyList<DatabaseTable> ta
 				{
 					while (reader.Read())
 					{
+						var columns = reader.IsDBNull(3) ? string.Empty : reader.GetString(3);
+						if (string.IsNullOrEmpty(columns))
+						{
+							continue;
+						}
+
 						var index = new DatabaseIndex
 						{
 							Table = table,
@@ -344,7 +351,7 @@ private void GetIndexes(DbConnection connection, IReadOnlyList<DatabaseTable> ta
 							IsUnique = reader.GetBoolean(1),
 						};
 
-						foreach (var column in reader.GetString(3).Split(','))
+						foreach (var column in columns.Split(','))
 						{
 							index.Columns.Add(table.Columns.Single(y => y.Name == column.Trim()));
 						}