store: Revamp query rewriting

1. Do not use CTE's to inject a view of a table at a certain block. Instead
   rewrite the 'from' clause
2. Do not turn bytea columns into string columns since that is hugely
   wasteful

Author: lutter

store/postgres/src/query_store.rs

@@ -30,7 +30,7 @@ impl QueryStore {
     ) -> Self {
         let sql_parser = store
             .find_layout(site.clone())
-            .map(|layout| Parser::new(layout));
+            .map(|layout| Parser::new(layout, BLOCK_NUMBER_MAX));
         QueryStore {
             site,
             replica_id,

store/postgres/src/sql/parser.rs

@@ -1,21 +1,23 @@
 use super::{constants::SQL_DIALECT, validation::Validator};
 use crate::relational::Layout;
 use anyhow::{anyhow, Ok, Result};
+use graph::prelude::BlockNumber;
 use std::sync::Arc;
 
 pub struct Parser {
     layout: Arc<Layout>,
+    block: BlockNumber,
 }
 
 impl Parser {
-    pub fn new(layout: Arc<Layout>) -> Self {
-        Self { layout }
+    pub fn new(layout: Arc<Layout>, block: BlockNumber) -> Self {
+        Self { layout, block }
     }
 
     pub fn parse_and_validate(&self, sql: &str) -> Result<String> {
         let mut statements = sqlparser::parser::Parser::parse_sql(&SQL_DIALECT, sql)?;
 
-        let mut validator = Validator::new(&self.layout);
+        let mut validator = Validator::new(&self.layout, self.block);
         validator.validate_statements(&mut statements)?;
 
         let statement = statements
@@ -33,6 +35,8 @@ impl Parser {
 #[cfg(test)]
 mod test {
 
+    use graph::prelude::BLOCK_NUMBER_MAX;
+
     use crate::sql::test::make_layout;
 
     use super::*;
@@ -93,7 +97,7 @@ mod test {
         ";
 
     fn parse_and_validate(sql: &str) -> Result<String, anyhow::Error> {
-        let parser = Parser::new(Arc::new(make_layout(TEST_GQL)));
+        let parser = Parser::new(Arc::new(make_layout(TEST_GQL)), BLOCK_NUMBER_MAX);
 
         parser.parse_and_validate(sql)
     }
@@ -114,6 +118,10 @@ mod test {
         let query =
             parse_and_validate("select symbol, address from token where decimals > 10").unwrap();
 
+        assert_eq!(
+            query,
+            r#"select to_jsonb(sub.*) as data from ( SELECT symbol, address FROM (SELECT * FROM "sgd0815"."token" WHERE block_range @> 2147483647) AS token WHERE decimals > 10 ) as sub"#
+        );
         println!("{}", query);
     }
 }

store/postgres/src/sql/validation.rs

@@ -1,3 +1,4 @@
+use graph::prelude::BlockNumber;
 use sqlparser::ast::{
     Expr, Ident, ObjectName, Query, SetExpr, Statement, TableAlias, TableFactor, VisitMut,
     VisitorMut,
@@ -6,6 +7,7 @@ use sqlparser::parser::Parser;
 use std::result::Result;
 use std::{collections::HashSet, ops::ControlFlow};
 
+use crate::block_range::{BLOCK_COLUMN, BLOCK_RANGE_COLUMN};
 use crate::relational::Layout;
 
 use super::constants::{ALLOWED_FUNCTIONS, SQL_DIALECT};
@@ -25,13 +27,15 @@ pub enum Error {
 pub struct Validator<'a> {
     layout: &'a Layout,
     ctes: HashSet<String>,
+    block: BlockNumber,
 }
 
 impl<'a> Validator<'a> {
-    pub fn new(layout: &'a Layout) -> Self {
+    pub fn new(layout: &'a Layout, block: BlockNumber) -> Self {
         Self {
             layout,
             ctes: Default::default(),
+            block,
         }
     }
 
@@ -113,7 +117,17 @@ impl VisitorMut for Validator<'_> {
             };
 
             // Change 'from table [as alias]' to 'from (select * from table) as alias'
-            let query = format!("select * from {}", table.qualified_name);
+            let query = if table.immutable {
+                format!(
+                    "select * from {} where {} <= {}",
+                    table.qualified_name, BLOCK_COLUMN, self.block
+                )
+            } else {
+                format!(
+                    "select * from {} where {} @> {}",
+                    table.qualified_name, BLOCK_RANGE_COLUMN, self.block
+                )
+            };
             let Statement::Query(subquery) = Parser::parse_sql(&SQL_DIALECT, &query)
                 .unwrap()
                 .pop()
@@ -147,6 +161,8 @@ impl VisitorMut for Validator<'_> {
 
 #[cfg(test)]
 mod test {
+    use graph::prelude::BLOCK_NUMBER_MAX;
+
     use super::*;
     use crate::sql::{constants::SQL_DIALECT, test::make_layout};
 
@@ -170,7 +186,7 @@ mod test {
 
         let layout = make_layout(GQL);
 
-        let mut validator = Validator::new(&layout);
+        let mut validator = Validator::new(&layout, BLOCK_NUMBER_MAX);
 
         validator.validate_statements(&mut statements)
     }