diff --git a/src/test/kotlin/kestrel/PreparedStatementTest.kt b/src/test/kotlin/kestrel/PreparedStatementTest.kt
index eb044e0..9885fdc 100644
--- a/src/test/kotlin/kestrel/PreparedStatementTest.kt
+++ b/src/test/kotlin/kestrel/PreparedStatementTest.kt
@@ -154,3 +154,84 @@ class PreparedStatementTest {
         assertFailsWith<KestrelException> { run("EXECUTE byId()") }
     }
 
+    @Test
+    fun executeOfAnUnknownNameFails() {
+        assertFailsWith<KestrelException> { run("EXECUTE nope(1)") }
+    }
+
+    @Test
+    fun preparingTheSameNameTwiceFails() {
+        seedAccounts()
+        run("PREPARE byId AS SELECT name FROM accounts WHERE id = \$1")
+        assertFailsWith<KestrelException> { run("PREPARE byId AS SELECT balance FROM accounts WHERE id = \$1") }
+    }
+
+    @Test
+    fun deallocateRemovesAPreparedStatementSoExecuteNoLongerFindsIt() {
+        seedAccounts()
+        run("PREPARE byId AS SELECT name FROM accounts WHERE id = \$1")
+        assertEquals(DeallocateResult("byId", all = false), run("DEALLOCATE byId").single())
+        assertFailsWith<KestrelException> { run("EXECUTE byId(1)") }
+    }
+
+    @Test
+    fun deallocatingAnUnknownNameFails() {
+        assertFailsWith<KestrelException> { run("DEALLOCATE nope") }
+    }
+
+    @Test
+    fun deallocateAllRemovesEveryPreparedStatement() {
+        seedAccounts()
+        run("PREPARE p1 AS SELECT name FROM accounts WHERE id = \$1")
+        run("PREPARE p2 AS SELECT balance FROM accounts WHERE id = \$1")
+        assertEquals(DeallocateResult(null, all = true), run("DEALLOCATE ALL").single())
+        assertFailsWith<KestrelException> { run("EXECUTE p1(1)") }
+        assertFailsWith<KestrelException> { run("EXECUTE p2(1)") }
+    }
+
+    @Test
+    fun aNameCanBeReparedAfterBeingDeallocated() {
+        seedAccounts()
+        run("PREPARE byId AS SELECT name FROM accounts WHERE id = \$1")
+        run("DEALLOCATE byId")
+        run("PREPARE byId AS SELECT balance FROM accounts WHERE id = \$1")
+        assertEquals(listOf(listOf(Value.IntegerValue(100))), select("EXECUTE byId(1)").rows)
+    }
+
+    @Test
+    fun preparedStatementsAreNotUndoneByRollback() {
+        seedAccounts()
+        run("BEGIN")
+        run("PREPARE byId AS SELECT name FROM accounts WHERE id = \$1")
+        run("ROLLBACK")
+        // Session-scoped, deliberately outside the transactional catalog snapshot - see
+        // PrepareStatement's own doc for why.
+        assertEquals(listOf(listOf(Value.TextValue("ada"))), select("EXECUTE byId(1)").rows)
+    }
+
+    @Test
+    fun executeArgumentsMustBeConstantNotColumnReferences() {
+        seedAccounts()
+        run("PREPARE byId AS SELECT name FROM accounts WHERE id = \$1")
+        assertFailsWith<KestrelException> { run("EXECUTE byId(id)") }
+    }
+
+    @Test
+    fun aParameterInTheSelectListDoesNotNeedToAppearInGroupBy() {
+        seedAccounts()
+        run("PREPARE report AS SELECT \$1, COUNT(*) FROM accounts GROUP BY name")
+        val result = select("EXECUTE report('label')")
+        assertEquals(3, result.rows.size)
+        result.rows.forEach { row -> assertEquals(Value.TextValue("label"), row[0]) }
+    }
+
+    @Test
+    fun aParameterTypedDirectlyOutsidePrepareParsesButOnlyFailsAtEvaluationTime() {
+        seedAccounts()
+        // $1 is structurally legal wherever any expression is (no PREPARE context exists at parse
+        // time to reject it) - GROUP BY validation lets it through exactly like a literal would, and
+        // it only fails once evaluation actually needs a real value for it.
+        val exception = assertFailsWith<KestrelException> { run("SELECT \$1, COUNT(*) FROM accounts GROUP BY name") }
+        assertTrue(exception.message!!.contains("parameter reference"), exception.message)
+    }
+}