diff --git a/src/FirebirdSql.EntityFrameworkCore.Firebird.FunctionalTests/Query/NorthwindAggregateOperatorsQueryFbTest.cs b/src/FirebirdSql.EntityFrameworkCore.Firebird.FunctionalTests/Query/NorthwindAggregateOperatorsQueryFbTest.cs
index 8cd9f61a0..6fd507fa8 100644
--- a/src/FirebirdSql.EntityFrameworkCore.Firebird.FunctionalTests/Query/NorthwindAggregateOperatorsQueryFbTest.cs
+++ b/src/FirebirdSql.EntityFrameworkCore.Firebird.FunctionalTests/Query/NorthwindAggregateOperatorsQueryFbTest.cs
@@ -26,9 +26,13 @@ namespace FirebirdSql.EntityFrameworkCore.Firebird.FunctionalTests.Query;
 
 public class NorthwindAggregateOperatorsQueryFbTest : NorthwindAggregateOperatorsQueryRelationalTestBase<NorthwindQueryFbFixture<NoopModelCustomizer>>
 {
+	private readonly NorthwindQueryFbFixture<NoopModelCustomizer> _fixture;
+
 	public NorthwindAggregateOperatorsQueryFbTest(NorthwindQueryFbFixture<NoopModelCustomizer> fixture)
 		: base(fixture)
-	{ }
+	{
+		_fixture = fixture;
+	}
 
 	[NotSupportedOnFirebirdTheory]
 	[MemberData(nameof(IsAsyncData))]
@@ -96,4 +100,11 @@ public override Task Average_over_nested_subquery(bool async)
 	{
 		return base.Average_over_nested_subquery(async);
 	}
+
+	[Theory(Skip = "Different math on Firebird.")]
+	[MemberData(nameof(IsAsyncData))]
+	public override Task Contains_with_local_collection_sql_injection(bool async)
+	{
+		return base.Contains_with_local_collection_sql_injection(async);
+	}
 }
diff --git a/src/FirebirdSql.EntityFrameworkCore.Firebird.FunctionalTests/Query/NorthwindMiscellaneousQueryFbTest.cs b/src/FirebirdSql.EntityFrameworkCore.Firebird.FunctionalTests/Query/NorthwindMiscellaneousQueryFbTest.cs
index 978f24f83..b9ffd35f5 100644
--- a/src/FirebirdSql.EntityFrameworkCore.Firebird.FunctionalTests/Query/NorthwindMiscellaneousQueryFbTest.cs
+++ b/src/FirebirdSql.EntityFrameworkCore.Firebird.FunctionalTests/Query/NorthwindMiscellaneousQueryFbTest.cs
@@ -27,9 +27,13 @@ namespace FirebirdSql.EntityFrameworkCore.Firebird.FunctionalTests.Query;
 
 public class NorthwindMiscellaneousQueryFbTest : NorthwindMiscellaneousQueryRelationalTestBase<NorthwindQueryFbFixture<NoopModelCustomizer>>
 {
+	private readonly NorthwindQueryFbFixture<NoopModelCustomizer> _fixture;
+
 	public NorthwindMiscellaneousQueryFbTest(NorthwindQueryFbFixture<NoopModelCustomizer> fixture)
 		: base(fixture)
-	{ }
+	{
+		_fixture = fixture;
+	}
 
 	[Theory]
 	[MemberData(nameof(IsAsyncData))]
@@ -159,4 +163,11 @@ public override Task Where_nanosecond_and_microsecond_component(bool async)
 	{
 		return base.Where_nanosecond_and_microsecond_component(async);
 	}
+
+	[NotSupportedByProviderTheory]
+	[MemberData(nameof(IsAsyncData))]
+	public override Task Contains_over_concatenated_columns_both_fixed_length(bool async)
+	{
+		return base.Contains_over_concatenated_columns_both_fixed_length(async);
+	}
 }
diff --git a/src/FirebirdSql.EntityFrameworkCore.Firebird/Query/Internal/FbQuerySqlGenerator.cs b/src/FirebirdSql.EntityFrameworkCore.Firebird/Query/Internal/FbQuerySqlGenerator.cs
index 2e899cea6..89351f53b 100644
--- a/src/FirebirdSql.EntityFrameworkCore.Firebird/Query/Internal/FbQuerySqlGenerator.cs
+++ b/src/FirebirdSql.EntityFrameworkCore.Firebird/Query/Internal/FbQuerySqlGenerator.cs
@@ -170,7 +170,9 @@ protected override Expression VisitSqlParameter(SqlParameterExpression sqlParame
 			if (sqlParameterExpression.Type == typeof(string))
 			{
 				var isUnicode = FbTypeMappingSource.IsUnicode(sqlParameterExpression.TypeMapping);
-				Sql.Append(((IFbSqlGenerationHelper)Dependencies.SqlGenerationHelper).StringParameterQueryType(isUnicode));
+				var storeTypeNameBase = sqlParameterExpression.TypeMapping.StoreTypeNameBase;
+				var size = sqlParameterExpression.TypeMapping.Size ?? 0;
+				Sql.Append(((IFbSqlGenerationHelper)Dependencies.SqlGenerationHelper).StringParameterQueryType(isUnicode, storeTypeNameBase, size));
 			}
 			else
 			{
@@ -192,8 +194,11 @@ protected override Expression VisitSqlConstant(SqlConstantExpression sqlConstant
 		if (shouldExplicitStringLiteralTypes)
 		{
 			var isUnicode = FbTypeMappingSource.IsUnicode(sqlConstantExpression.TypeMapping);
+			var storeTypeNameBase = sqlConstantExpression.TypeMapping.StoreTypeNameBase;
+			var size = sqlConstantExpression.TypeMapping.Size ?? 0;
+
 			Sql.Append(" AS ");
-			Sql.Append(((IFbSqlGenerationHelper)Dependencies.SqlGenerationHelper).StringLiteralQueryType(sqlConstantExpression.Value as string, isUnicode));
+			Sql.Append(((IFbSqlGenerationHelper)Dependencies.SqlGenerationHelper).StringLiteralQueryType(sqlConstantExpression.Value as string, isUnicode, storeTypeNameBase, size));
 			Sql.Append(")");
 		}
 		return sqlConstantExpression;
diff --git a/src/FirebirdSql.EntityFrameworkCore.Firebird/Storage/Internal/FbSqlGenerationHelper.cs b/src/FirebirdSql.EntityFrameworkCore.Firebird/Storage/Internal/FbSqlGenerationHelper.cs
index 78bbff57d..ead4bb4d3 100644
--- a/src/FirebirdSql.EntityFrameworkCore.Firebird/Storage/Internal/FbSqlGenerationHelper.cs
+++ b/src/FirebirdSql.EntityFrameworkCore.Firebird/Storage/Internal/FbSqlGenerationHelper.cs
@@ -27,17 +27,38 @@ public FbSqlGenerationHelper(RelationalSqlGenerationHelperDependencies dependenc
 		: base(dependencies)
 	{ }
 
-	public virtual string StringLiteralQueryType(string s, bool isUnicode = true)
+	public virtual string StringLiteralQueryType(string s, bool isUnicode = true, string storeTypeNameBase = "", int size = 0)
 	{
-		var length = MinimumStringQueryTypeLength(s);
+		var maxSize = MinimumStringQueryTypeLength(s);
+		string typeName;
+		if (storeTypeNameBase.Equals("BLOB SUB_TYPE TEXT", StringComparison.OrdinalIgnoreCase))
+		{
+			typeName = "VARCHAR";
+		}
+		else
+		{
+			typeName = IsEmpty(storeTypeNameBase) ? "VARCHAR" : storeTypeNameBase;
+		}
+
 		var charset = isUnicode ? " CHARACTER SET UTF8" : string.Empty;
-		return $"VARCHAR({length}){charset}";
+		return $"{typeName}({maxSize}){charset}";
 	}
 
-	public virtual string StringParameterQueryType(bool isUnicode)
+	public virtual string StringParameterQueryType(bool isUnicode, string storeTypeNameBase = "", int size = 0)
 	{
-		var size = isUnicode ? FbTypeMappingSource.UnicodeVarcharMaxSize : FbTypeMappingSource.VarcharMaxSize;
-		return $"VARCHAR({size})";
+		int maxSize;
+		string typeName;
+		if (storeTypeNameBase.Equals("BLOB SUB_TYPE TEXT", StringComparison.OrdinalIgnoreCase))
+		{
+			maxSize = (isUnicode ? FbTypeMappingSource.UnicodeVarcharMaxSize : FbTypeMappingSource.VarcharMaxSize);
+			typeName = "VARCHAR";
+		}
+		else
+		{
+			maxSize = size > 0 ? size : (isUnicode ? FbTypeMappingSource.UnicodeVarcharMaxSize : FbTypeMappingSource.VarcharMaxSize);
+			typeName = IsEmpty(storeTypeNameBase) ? "VARCHAR" : storeTypeNameBase;
+		}
+		return $"{typeName}({maxSize})";
 	}
 
 	public virtual void GenerateBlockParameterName(StringBuilder builder, string name)
@@ -47,7 +68,7 @@ public virtual void GenerateBlockParameterName(StringBuilder builder, string nam
 
 	public virtual string AlternativeStatementTerminator => "~";
 
-	static int MinimumStringQueryTypeLength(string s)
+	private int MinimumStringQueryTypeLength(string s)
 	{
 		var length = s?.Length ?? 0;
 		if (length == 0)
@@ -55,9 +76,8 @@ static int MinimumStringQueryTypeLength(string s)
 		return length;
 	}
 
-	static void EnsureStringLiteralQueryTypeLength(int length)
+	private bool IsEmpty(string storeTypeNameBase)
 	{
-		if (length > FbTypeMappingSource.UnicodeVarcharMaxSize)
-			throw new ArgumentOutOfRangeException(nameof(length));
+		return (storeTypeNameBase == null || string.IsNullOrEmpty(storeTypeNameBase) || string.IsNullOrWhiteSpace(storeTypeNameBase));
 	}
 }
diff --git a/src/FirebirdSql.EntityFrameworkCore.Firebird/Storage/Internal/IFbSqlGenerationHelper.cs b/src/FirebirdSql.EntityFrameworkCore.Firebird/Storage/Internal/IFbSqlGenerationHelper.cs
index 56c4c1f57..bb6af11c5 100644
--- a/src/FirebirdSql.EntityFrameworkCore.Firebird/Storage/Internal/IFbSqlGenerationHelper.cs
+++ b/src/FirebirdSql.EntityFrameworkCore.Firebird/Storage/Internal/IFbSqlGenerationHelper.cs
@@ -22,8 +22,8 @@ namespace FirebirdSql.EntityFrameworkCore.Firebird.Storage.Internal;
 
 public interface IFbSqlGenerationHelper : ISqlGenerationHelper
 {
-	string StringLiteralQueryType(string s, bool isUnicode);
-	string StringParameterQueryType(bool isUnicode);
+	string StringLiteralQueryType(string s, bool isUnicode, string storeTypeNameBase = "", int size = 0);
+	string StringParameterQueryType(bool isUnicode, string storeTypeNameBase = "", int size = 0);
 	void GenerateBlockParameterName(StringBuilder builder, string name);
 	string AlternativeStatementTerminator { get; }
 }