diff --git a/01.workspace/heave/src/fun/sqlite_build_params.rs b/01.workspace/heave/src/fun/sqlite_build_params.rs
index fa9e83c..bd01669 100644
--- a/01.workspace/heave/src/fun/sqlite_build_params.rs
+++ b/01.workspace/heave/src/fun/sqlite_build_params.rs
@@ -4,7 +4,7 @@ use rusqlite::*;
 pub fn run(filter: &Filter) -> Result<Vec<Box<dyn ToSql>>, FailedTo> {
     let mut params: Vec<Box<dyn ToSql>> = Vec::new();
     for condition in filter.conditions() {
-        match condition.1 {
+        match condition.2 {
             Condition::Bool(value) => params.push(Box::new(value)),
         }
     }
diff --git a/01.workspace/heave/src/fun/sqlite_build_statement.rs b/01.workspace/heave/src/fun/sqlite_build_statement.rs
index 6583f9a..105bd93 100644
--- a/01.workspace/heave/src/fun/sqlite_build_statement.rs
+++ b/01.workspace/heave/src/fun/sqlite_build_statement.rs
@@ -4,7 +4,7 @@ const BASE_SELECT: &str = r#"SELECT * FROM entity WHERE 1=1"#;
 
 pub fn run(filter: &Filter) -> Result<String, FailedTo> {
     let mut statement = String::from(BASE_SELECT);
-    for (i, (name, condition)) in filter.conditions().enumerate() {
+    for (i, (name, _comparison, condition)) in filter.conditions().enumerate() {
         let fragment = match *condition {
             Condition::Bool(_) => format!(
                 " AND id IN (SELECT entity_id FROM attribute WHERE id = '{}' AND value_bool = ?{})",
diff --git a/01.workspace/heave/src/lib.rs b/01.workspace/heave/src/lib.rs
index e07cdb7..70e9621 100644
--- a/01.workspace/heave/src/lib.rs
+++ b/01.workspace/heave/src/lib.rs
@@ -9,6 +9,7 @@ mod tst;
 
 pub(crate) use crate::str::attribute::O as Attribute;
 pub use crate::str::catalog::O as Catalog;
+pub use crate::str::comparison::E as Comparison;
 pub use crate::str::condition::E as Condition;
 pub use crate::str::entity::O as Entity;
 pub use crate::str::entity_state::EntityState;
diff --git a/01.workspace/heave/src/str/comparison.rs b/01.workspace/heave/src/str/comparison.rs
new file mode 100644
index 0000000..8766ab7
--- /dev/null
+++ b/01.workspace/heave/src/str/comparison.rs
@@ -0,0 +1,4 @@
+#[derive(Debug, PartialEq, PartialOrd, Eq, Ord, Clone, Copy, Hash)]
+pub enum E {
+    Equal,
+}
diff --git a/01.workspace/heave/src/str/filter.rs b/01.workspace/heave/src/str/filter.rs
index 0d7546d..df53525 100644
--- a/01.workspace/heave/src/str/filter.rs
+++ b/01.workspace/heave/src/str/filter.rs
@@ -2,7 +2,7 @@ use crate::*;
 
 #[derive(Debug, Default, PartialEq, Clone)]
 pub struct O {
-    conditions: Vec<(String, Condition)>,
+    conditions: Vec<(String, Comparison, Condition)>,
 }
 
 impl Filter {
@@ -12,11 +12,14 @@ impl Filter {
         }
     }
     pub fn with_bool(mut self, attribute_name: &str, value: bool) -> Self {
-        self.conditions
-            .push((attribute_name.to_string(), Condition::Bool(value)));
+        self.conditions.push((
+            attribute_name.to_string(),
+            Comparison::Equal,
+            Condition::Bool(value),
+        ));
         self
     }
-    pub(crate) fn conditions(&self) -> impl Iterator<Item = &(String, Condition)> {
+    pub(crate) fn conditions(&self) -> impl Iterator<Item = &(String, Comparison, Condition)> {
         self.conditions.iter()
     }
 }
diff --git a/01.workspace/heave/src/str/mod.rs b/01.workspace/heave/src/str/mod.rs
index df2a220..c50b2e4 100644
--- a/01.workspace/heave/src/str/mod.rs
+++ b/01.workspace/heave/src/str/mod.rs
@@ -1,5 +1,6 @@
 pub mod attribute;
 pub mod catalog;
+pub mod comparison;
 pub mod condition;
 pub mod entity;
 pub mod entity_state;