diff --git a/optd-persistent/src/bin/init.rs b/optd-persistent/src/bin/init.rs
index 9cc07e2..b21f6f0 100644
--- a/optd-persistent/src/bin/init.rs
+++ b/optd-persistent/src/bin/init.rs
@@ -276,6 +276,7 @@ async fn init_all_tables() -> Result<(), sea_orm::error::DbErr> {
         latest_winner: Set(None),
         in_progress: Set(true),
         is_optimized: Set(false),
+        parent_id: Set(None),
     };
     cascades_group::Entity::insert(cascades_group)
         .exec(&db)
@@ -288,7 +289,6 @@ async fn init_all_tables() -> Result<(), sea_orm::error::DbErr> {
         group_id: Set(1),
         fingerprint: Set(12345),
         variant_tag: Set(0),
-        data: Set(json!(r#"{"expr": "index_scan"}"#)),
     };
     logical_expression::Entity::insert(logical_expression)
         .exec(&db)
@@ -301,7 +301,6 @@ async fn init_all_tables() -> Result<(), sea_orm::error::DbErr> {
         group_id: Set(1),
         fingerprint: Set(12345),
         variant_tag: Set(0),
-        data: Set(json!(r#"{"expr": "index_scan"}"#)),
     };
     physical_expression::Entity::insert(physical_expression)
         .exec(&db)
diff --git a/optd-persistent/src/entities/attribute.rs b/optd-persistent/src/entities/attribute.rs
index aa312c0..f45d04a 100644
--- a/optd-persistent/src/entities/attribute.rs
+++ b/optd-persistent/src/entities/attribute.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/attribute_constraint_junction.rs b/optd-persistent/src/entities/attribute_constraint_junction.rs
index 7c61c72..e1d8052 100644
--- a/optd-persistent/src/entities/attribute_constraint_junction.rs
+++ b/optd-persistent/src/entities/attribute_constraint_junction.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/attribute_foreign_constraint_junction.rs b/optd-persistent/src/entities/attribute_foreign_constraint_junction.rs
index f219a39..c2f0b61 100644
--- a/optd-persistent/src/entities/attribute_foreign_constraint_junction.rs
+++ b/optd-persistent/src/entities/attribute_foreign_constraint_junction.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/cascades_group.rs b/optd-persistent/src/entities/cascades_group.rs
index 9ea79d1..8be9f4f 100644
--- a/optd-persistent/src/entities/cascades_group.rs
+++ b/optd-persistent/src/entities/cascades_group.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
@@ -10,10 +10,19 @@ pub struct Model {
     pub latest_winner: Option<i32>,
     pub in_progress: bool,
     pub is_optimized: bool,
+    pub parent_id: Option<i32>,
 }
 
 #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
 pub enum Relation {
+    #[sea_orm(
+        belongs_to = "Entity",
+        from = "Column::ParentId",
+        to = "Column::Id",
+        on_update = "Cascade",
+        on_delete = "SetNull"
+    )]
+    SelfRef,
     #[sea_orm(has_many = "super::group_winner::Entity")]
     GroupWinner,
     #[sea_orm(has_many = "super::logical_children::Entity")]
diff --git a/optd-persistent/src/entities/constraint_metadata.rs b/optd-persistent/src/entities/constraint_metadata.rs
index 8adf1d7..5630e3e 100644
--- a/optd-persistent/src/entities/constraint_metadata.rs
+++ b/optd-persistent/src/entities/constraint_metadata.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/database_metadata.rs b/optd-persistent/src/entities/database_metadata.rs
index 98106d6..190bc73 100644
--- a/optd-persistent/src/entities/database_metadata.rs
+++ b/optd-persistent/src/entities/database_metadata.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/event.rs b/optd-persistent/src/entities/event.rs
index ad9157d..c26c7b1 100644
--- a/optd-persistent/src/entities/event.rs
+++ b/optd-persistent/src/entities/event.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/group_winner.rs b/optd-persistent/src/entities/group_winner.rs
index 32cbcb4..efd8661 100644
--- a/optd-persistent/src/entities/group_winner.rs
+++ b/optd-persistent/src/entities/group_winner.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/index_metadata.rs b/optd-persistent/src/entities/index_metadata.rs
index 47263b7..49a1ea2 100644
--- a/optd-persistent/src/entities/index_metadata.rs
+++ b/optd-persistent/src/entities/index_metadata.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/logical_children.rs b/optd-persistent/src/entities/logical_children.rs
index 120641f..92d53bd 100644
--- a/optd-persistent/src/entities/logical_children.rs
+++ b/optd-persistent/src/entities/logical_children.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/logical_expression.rs b/optd-persistent/src/entities/logical_expression.rs
index 6beff04..818c3ff 100644
--- a/optd-persistent/src/entities/logical_expression.rs
+++ b/optd-persistent/src/entities/logical_expression.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
@@ -10,7 +10,6 @@ pub struct Model {
     pub group_id: i32,
     pub fingerprint: i64,
     pub variant_tag: i16,
-    pub data: Json,
 }
 
 #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
@@ -25,6 +24,8 @@ pub enum Relation {
     CascadesGroup,
     #[sea_orm(has_many = "super::logical_children::Entity")]
     LogicalChildren,
+    #[sea_orm(has_many = "super::predicate_logical_expression_junction::Entity")]
+    PredicateLogicalExpressionJunction,
 }
 
 impl Related<super::logical_children::Entity> for Entity {
@@ -33,6 +34,12 @@ impl Related<super::logical_children::Entity> for Entity {
     }
 }
 
+impl Related<super::predicate_logical_expression_junction::Entity> for Entity {
+    fn to() -> RelationDef {
+        Relation::PredicateLogicalExpressionJunction.def()
+    }
+}
+
 impl Related<super::cascades_group::Entity> for Entity {
     fn to() -> RelationDef {
         super::logical_children::Relation::CascadesGroup.def()
@@ -46,4 +53,17 @@ impl Related<super::cascades_group::Entity> for Entity {
     }
 }
 
+impl Related<super::predicate::Entity> for Entity {
+    fn to() -> RelationDef {
+        super::predicate_logical_expression_junction::Relation::Predicate.def()
+    }
+    fn via() -> Option<RelationDef> {
+        Some(
+            super::predicate_logical_expression_junction::Relation::LogicalExpression
+                .def()
+                .rev(),
+        )
+    }
+}
+
 impl ActiveModelBehavior for ActiveModel {}
diff --git a/optd-persistent/src/entities/logical_property.rs b/optd-persistent/src/entities/logical_property.rs
index 755575c..f42ffdd 100644
--- a/optd-persistent/src/entities/logical_property.rs
+++ b/optd-persistent/src/entities/logical_property.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/mod.rs b/optd-persistent/src/entities/mod.rs
index 9434c2a..ab7c8f4 100644
--- a/optd-persistent/src/entities/mod.rs
+++ b/optd-persistent/src/entities/mod.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 pub mod prelude;
 
@@ -20,6 +20,10 @@ pub mod physical_expression;
 pub mod physical_expression_to_statistic_junction;
 pub mod physical_property;
 pub mod plan_cost;
+pub mod predicate;
+pub mod predicate_children;
+pub mod predicate_logical_expression_junction;
+pub mod predicate_physical_expression_junction;
 pub mod statistic;
 pub mod statistic_to_attribute_junction;
 pub mod table_metadata;
diff --git a/optd-persistent/src/entities/namespace_metadata.rs b/optd-persistent/src/entities/namespace_metadata.rs
index 8f63146..f3f3f37 100644
--- a/optd-persistent/src/entities/namespace_metadata.rs
+++ b/optd-persistent/src/entities/namespace_metadata.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/physical_children.rs b/optd-persistent/src/entities/physical_children.rs
index d8f9db0..18c1794 100644
--- a/optd-persistent/src/entities/physical_children.rs
+++ b/optd-persistent/src/entities/physical_children.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/physical_expression.rs b/optd-persistent/src/entities/physical_expression.rs
index 4876d35..be75e3a 100644
--- a/optd-persistent/src/entities/physical_expression.rs
+++ b/optd-persistent/src/entities/physical_expression.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
@@ -10,7 +10,6 @@ pub struct Model {
     pub group_id: i32,
     pub fingerprint: i64,
     pub variant_tag: i16,
-    pub data: Json,
 }
 
 #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
@@ -33,6 +32,8 @@ pub enum Relation {
     PhysicalProperty,
     #[sea_orm(has_many = "super::plan_cost::Entity")]
     PlanCost,
+    #[sea_orm(has_many = "super::predicate_physical_expression_junction::Entity")]
+    PredicatePhysicalExpressionJunction,
 }
 
 impl Related<super::group_winner::Entity> for Entity {
@@ -65,6 +66,12 @@ impl Related<super::plan_cost::Entity> for Entity {
     }
 }
 
+impl Related<super::predicate_physical_expression_junction::Entity> for Entity {
+    fn to() -> RelationDef {
+        Relation::PredicatePhysicalExpressionJunction.def()
+    }
+}
+
 impl Related<super::cascades_group::Entity> for Entity {
     fn to() -> RelationDef {
         super::physical_children::Relation::CascadesGroup.def()
@@ -78,6 +85,19 @@ impl Related<super::cascades_group::Entity> for Entity {
     }
 }
 
+impl Related<super::predicate::Entity> for Entity {
+    fn to() -> RelationDef {
+        super::predicate_physical_expression_junction::Relation::Predicate.def()
+    }
+    fn via() -> Option<RelationDef> {
+        Some(
+            super::predicate_physical_expression_junction::Relation::PhysicalExpression
+                .def()
+                .rev(),
+        )
+    }
+}
+
 impl Related<super::statistic::Entity> for Entity {
     fn to() -> RelationDef {
         super::physical_expression_to_statistic_junction::Relation::Statistic.def()
diff --git a/optd-persistent/src/entities/physical_expression_to_statistic_junction.rs b/optd-persistent/src/entities/physical_expression_to_statistic_junction.rs
index f8020bd..0332f02 100644
--- a/optd-persistent/src/entities/physical_expression_to_statistic_junction.rs
+++ b/optd-persistent/src/entities/physical_expression_to_statistic_junction.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/physical_property.rs b/optd-persistent/src/entities/physical_property.rs
index 51d98dc..944a94d 100644
--- a/optd-persistent/src/entities/physical_property.rs
+++ b/optd-persistent/src/entities/physical_property.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/plan_cost.rs b/optd-persistent/src/entities/plan_cost.rs
index 1acf101..a78083e 100644
--- a/optd-persistent/src/entities/plan_cost.rs
+++ b/optd-persistent/src/entities/plan_cost.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/predicate_children.rs b/optd-persistent/src/entities/predicate_children.rs
index 93ef3eb..a30e2d9 100644
--- a/optd-persistent/src/entities/predicate_children.rs
+++ b/optd-persistent/src/entities/predicate_children.rs
@@ -31,4 +31,19 @@ pub enum Relation {
     Predicate1,
 }
 
+pub struct PredicateChildrenLink;
+
+impl Linked for PredicateChildrenLink {
+    type FromEntity = super::predicate::Entity;
+
+    type ToEntity = super::predicate::Entity;
+
+    fn link(&self) -> Vec<sea_orm::LinkDef> {
+        vec![
+            super::predicate_children::Relation::Predicate2.def(),
+            super::predicate_children::Relation::Predicate1.def(),
+        ]
+    }
+}
+
 impl ActiveModelBehavior for ActiveModel {}
diff --git a/optd-persistent/src/entities/prelude.rs b/optd-persistent/src/entities/prelude.rs
index 753e58b..4f84202 100644
--- a/optd-persistent/src/entities/prelude.rs
+++ b/optd-persistent/src/entities/prelude.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 pub use super::attribute::Entity as Attribute;
 pub use super::attribute_constraint_junction::Entity as AttributeConstraintJunction;
@@ -18,6 +18,10 @@ pub use super::physical_expression::Entity as PhysicalExpression;
 pub use super::physical_expression_to_statistic_junction::Entity as PhysicalExpressionToStatisticJunction;
 pub use super::physical_property::Entity as PhysicalProperty;
 pub use super::plan_cost::Entity as PlanCost;
+pub use super::predicate::Entity as Predicate;
+pub use super::predicate_children::Entity as PredicateChildren;
+pub use super::predicate_logical_expression_junction::Entity as PredicateLogicalExpressionJunction;
+pub use super::predicate_physical_expression_junction::Entity as PredicatePhysicalExpressionJunction;
 pub use super::statistic::Entity as Statistic;
 pub use super::statistic_to_attribute_junction::Entity as StatisticToAttributeJunction;
 pub use super::table_metadata::Entity as TableMetadata;
diff --git a/optd-persistent/src/entities/statistic.rs b/optd-persistent/src/entities/statistic.rs
index 1eaf96b..303dc0c 100644
--- a/optd-persistent/src/entities/statistic.rs
+++ b/optd-persistent/src/entities/statistic.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/statistic_to_attribute_junction.rs b/optd-persistent/src/entities/statistic_to_attribute_junction.rs
index 63d23fb..4581dd0 100644
--- a/optd-persistent/src/entities/statistic_to_attribute_junction.rs
+++ b/optd-persistent/src/entities/statistic_to_attribute_junction.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/table_metadata.rs b/optd-persistent/src/entities/table_metadata.rs
index 35ea923..c31140c 100644
--- a/optd-persistent/src/entities/table_metadata.rs
+++ b/optd-persistent/src/entities/table_metadata.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/trigger.rs b/optd-persistent/src/entities/trigger.rs
index a5f9de8..1e3c763 100644
--- a/optd-persistent/src/entities/trigger.rs
+++ b/optd-persistent/src/entities/trigger.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/entities/versioned_statistic.rs b/optd-persistent/src/entities/versioned_statistic.rs
index c4533bf..112cc59 100644
--- a/optd-persistent/src/entities/versioned_statistic.rs
+++ b/optd-persistent/src/entities/versioned_statistic.rs
@@ -1,4 +1,4 @@
-//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.0
+//! `SeaORM` Entity, @generated by sea-orm-codegen 1.1.1
 
 use sea_orm::entity::prelude::*;
 
diff --git a/optd-persistent/src/main.rs b/optd-persistent/src/main.rs
index 165189e..13ea27f 100644
--- a/optd-persistent/src/main.rs
+++ b/optd-persistent/src/main.rs
@@ -46,11 +46,11 @@ async fn basic_demo() {
         group_id: group.id.clone(),
         fingerprint: ActiveValue::Set(42), // Example fingerprint
         variant_tag: ActiveValue::Set(1),  // Example variant tag
-        data: ActiveValue::Set(json!({ // Example operator
-            "type": "Scan",
-            "table": "lineitem",
-            "predicate": "l_quantity < 10",
-        })),
+        // data: ActiveValue::Set(json!({ // Example operator
+        //     "type": "Scan",
+        //     "table": "lineitem",
+        //     "predicate": "l_quantity < 10",
+        // })),
         ..Default::default()
     }
     .save(&db)
diff --git a/optd-persistent/src/memo/expression.rs b/optd-persistent/src/memo/expression.rs
index ff1590c..09e213d 100644
--- a/optd-persistent/src/memo/expression.rs
+++ b/optd-persistent/src/memo/expression.rs
@@ -31,43 +31,43 @@ pub enum PhysicalOperator {
 /// expressions are equivalent.
 ///
 /// TODO actually make efficient.
-fn fingerprint(variant_tag: i16, data: &serde_json::Value) -> i64 {
+fn fingerprint(variant_tag: i16) -> i64 {
     let mut hasher = DefaultHasher::new();
 
     variant_tag.hash(&mut hasher);
-    data.hash(&mut hasher);
+    // data.hash(&mut hasher);
 
     hasher.finish() as i64
 }
 
 impl logical_expression::Model {
     /// Creates a new logical expression with an unset `id` and `group_id`.
-    pub fn new(variant_tag: LogicalOperator, data: serde_json::Value) -> Self {
+    pub fn new(variant_tag: LogicalOperator) -> Self {
         let tag = variant_tag as i16;
-        let fingerprint = fingerprint(tag, &data);
+        let fingerprint = fingerprint(tag);
 
         Self {
             id: 0,
             group_id: 0,
             fingerprint,
             variant_tag: tag,
-            data,
+            // data,
         }
     }
 }
 
 impl physical_expression::Model {
     /// Creates a new physical expression with an unset `id` and `group_id`.
-    pub fn new(variant_tag: PhysicalOperator, data: serde_json::Value) -> Self {
+    pub fn new(variant_tag: PhysicalOperator) -> Self {
         let tag = variant_tag as i16;
-        let fingerprint = fingerprint(tag, &data);
+        let fingerprint = fingerprint(tag);
 
         Self {
             id: 0,
             group_id: 0,
             fingerprint,
             variant_tag: tag,
-            data,
+            // data,
         }
     }
 }
diff --git a/optd-persistent/src/migrator/memo/m20241029_000001_predicate_children.rs b/optd-persistent/src/migrator/memo/m20241029_000001_predicate_children.rs
index f3c0d10..073d968 100644
--- a/optd-persistent/src/migrator/memo/m20241029_000001_predicate_children.rs
+++ b/optd-persistent/src/migrator/memo/m20241029_000001_predicate_children.rs
@@ -31,6 +31,7 @@ impl MigrationTrait for Migration {
                     .foreign_key(
                         ForeignKey::create()
                             .from(PredicateChildren::Table, PredicateChildren::ParentId)
+                            .name("ParentId")
                             .to(Predicate::Table, Predicate::Id)
                             .on_delete(ForeignKeyAction::Cascade)
                             .on_update(ForeignKeyAction::Cascade),
@@ -39,6 +40,7 @@ impl MigrationTrait for Migration {
                     .foreign_key(
                         ForeignKey::create()
                             .from(PredicateChildren::Table, PredicateChildren::ChildId)
+                            .name("ChildId")
                             .to(Predicate::Table, Predicate::Id)
                             .on_delete(ForeignKeyAction::Cascade)
                             .on_update(ForeignKeyAction::Cascade),