diff --git a/docs/source/functions.rst b/docs/source/functions.rst
index 18618d73..af37a1d8 100644
--- a/docs/source/functions.rst
+++ b/docs/source/functions.rst
@@ -627,7 +627,7 @@ Empty matches::
 
 
 --------------------
-Misc functions
+Timestamp functions
 --------------------
 
 .. function:: now()
@@ -638,4 +638,8 @@ Misc functions
 
     Interpret ``ts`` as seconds since the epoch and format as a string according to `RFC3339 <https://www.rfc-editor.org/rfc/rfc3339>`_.
 
-    If a second string argument is provided, it is interpreted as a `timezone <https://en.wikipedia.org/wiki/Tz_database>`_ and used to format the timestamp.
\ No newline at end of file
+    If a second string argument is provided, it is interpreted as a `timezone <https://en.wikipedia.org/wiki/Tz_database>`_ and used to format the timestamp.
+
+.. function:: parse_timestamp(str)
+
+    Parse ``str`` into seconds since the epoch according to RFC3339.
\ No newline at end of file
diff --git a/src/data/expr.rs b/src/data/expr.rs
index ef31a870..00e353ff 100644
--- a/src/data/expr.rs
+++ b/src/data/expr.rs
@@ -336,7 +336,7 @@ impl Expr {
                             if target == symb {
                                 let tar_val = match val.get_int() {
                                     Some(i) => DataValue::from(i),
-                                    None => val.clone()
+                                    None => val.clone(),
                                 };
                                 return Ok(ValueRange::lower_bound(tar_val));
                             }
@@ -347,7 +347,7 @@ impl Expr {
                             if target == symb {
                                 let tar_val = match val.get_float() {
                                     Some(i) => DataValue::from(i),
-                                    None => val.clone()
+                                    None => val.clone(),
                                 };
                                 return Ok(ValueRange::upper_bound(tar_val));
                             }
@@ -361,7 +361,7 @@ impl Expr {
                             if target == symb {
                                 let tar_val = match val.get_float() {
                                     Some(i) => DataValue::from(i),
-                                    None => val.clone()
+                                    None => val.clone(),
                                 };
 
                                 return Ok(ValueRange::upper_bound(tar_val));
@@ -373,7 +373,7 @@ impl Expr {
                             if target == symb {
                                 let tar_val = match val.get_int() {
                                     Some(i) => DataValue::from(i),
-                                    None => val.clone()
+                                    None => val.clone(),
                                 };
 
                                 return Ok(ValueRange::lower_bound(tar_val));
@@ -653,6 +653,7 @@ pub(crate) fn get_op(name: &str) -> Option<&'static Op> {
         "uuid_timestamp" => &OP_UUID_TIMESTAMP,
         "now" => &OP_NOW,
         "format_timestamp" => &OP_FORMAT_TIMESTAMP,
+        "parse_timestamp" => &OP_PARSE_TIMESTAMP,
         _ => return None,
     })
 }
diff --git a/src/data/functions.rs b/src/data/functions.rs
index 52085e13..8e7ae395 100644
--- a/src/data/functions.rs
+++ b/src/data/functions.rs
@@ -3,7 +3,7 @@ use std::ops::{Div, Rem};
 use std::str::FromStr;
 use std::time::{SystemTime, UNIX_EPOCH};
 
-use chrono::{TimeZone, Utc};
+use chrono::{DateTime, TimeZone, Utc};
 use itertools::Itertools;
 use miette::{bail, ensure, miette, Result};
 use num_traits::FloatConst;
@@ -1417,7 +1417,8 @@ pub(crate) fn op_format_timestamp(args: &[DataValue]) -> Result<DataValue> {
             let tz_s = tz_v.get_string().ok_or_else(|| {
                 miette!("'format_timestamp' timezone specification requires a string")
             })?;
-            let tz = chrono_tz::Tz::from_str(tz_s).map_err(|_| miette!("bad timezone specification: {}", tz_s))?;
+            let tz = chrono_tz::Tz::from_str(tz_s)
+                .map_err(|_| miette!("bad timezone specification: {}", tz_s))?;
             let dt_tz = dt.with_timezone(&tz);
             let s = SmartString::from(dt_tz.to_rfc3339());
             Ok(DataValue::Str(s))
@@ -1429,6 +1430,18 @@ pub(crate) fn op_format_timestamp(args: &[DataValue]) -> Result<DataValue> {
     }
 }
 
+define_op!(OP_PARSE_TIMESTAMP, 1, false);
+pub(crate) fn op_parse_timestamp(args: &[DataValue]) -> Result<DataValue> {
+    let s = args[0]
+        .get_string()
+        .ok_or_else(|| miette!("'parse_timestamp' expects a string"))?;
+    let dt = DateTime::parse_from_rfc3339(s).map_err(|_| miette!("bad datetime: {}", s))?;
+    let st: SystemTime = dt.into();
+    Ok(DataValue::from(
+        st.duration_since(UNIX_EPOCH).unwrap().as_secs_f64(),
+    ))
+}
+
 define_op!(OP_RAND_UUID_V1, 0, false);
 pub(crate) fn op_rand_uuid_v1(_args: &[DataValue]) -> Result<DataValue> {
     let mut rng = rand::thread_rng();
diff --git a/src/data/tests/functions.rs b/src/data/tests/functions.rs
index 59224fb6..480cf871 100644
--- a/src/data/tests/functions.rs
+++ b/src/data/tests/functions.rs
@@ -1328,5 +1328,6 @@ fn test_uuid() {
 fn test_now() {
     let now = op_now(&[]).unwrap();
     assert!(matches!(now, DataValue::Num(_)));
-    op_format_timestamp(&[now]).unwrap();
+    let s = op_format_timestamp(&[now]).unwrap();
+    let _dt = op_parse_timestamp(&[s]).unwrap();
 }
\ No newline at end of file
diff --git a/src/query/relation.rs b/src/query/relation.rs
index 101985a3..5570053b 100644
--- a/src/query/relation.rs
+++ b/src/query/relation.rs
@@ -756,6 +756,7 @@ impl RelationRA {
             left_to_prefix_indices.push(left_join_indices[*idx]);
         }
 
+        // TODO don't build the whole thing is prefix scan suffices
         let mut right_join_vals = BTreeSet::new();
         for tuple in self.storage.scan_all(tx) {
             let tuple = tuple?;