From a9c09f33cbe58ba50704939c190fe7d44d7f8f59 Mon Sep 17 00:00:00 2001
From: Srikanth Chekuri <srikanth.chekuri92@gmail.com>
Date: Wed, 23 Apr 2025 14:44:10 +0530
Subject: [PATCH] chore: always add reserved vars (#7689)

---
 go.mod                                |  2 +-
 go.sum                                |  6 ++----
 pkg/variables/clickhouse/transform.go | 17 +++++++++++++++--
 pkg/variables/reserved_vars.go        | 14 ++++++++++++++
 4 files changed, 32 insertions(+), 7 deletions(-)
 create mode 100644 pkg/variables/reserved_vars.go

diff --git a/go.mod b/go.mod
index f5b29cb91d..b4e0b95fe1 100644
--- a/go.mod
+++ b/go.mod
@@ -6,7 +6,7 @@ toolchain go1.22.11
 
 require (
 	dario.cat/mergo v1.0.1
-	github.com/AfterShip/clickhouse-sql-parser v0.4.4
+	github.com/AfterShip/clickhouse-sql-parser v0.4.7
 	github.com/ClickHouse/clickhouse-go/v2 v2.30.0
 	github.com/DATA-DOG/go-sqlmock v1.5.2
 	github.com/SigNoz/govaluate v0.0.0-20240203125216-988004ccc7fd
diff --git a/go.sum b/go.sum
index 551fdbceba..a1905d8f24 100644
--- a/go.sum
+++ b/go.sum
@@ -64,8 +64,8 @@ dario.cat/mergo v1.0.1/go.mod h1:uNxQE+84aUszobStD9th8a29P2fMDhsBdgRYvZOxGmk=
 dmitri.shuralyov.com/gpu/mtl v0.0.0-20190408044501-666a987793e9/go.mod h1:H6x//7gZCb22OMCxBHrMx7a5I7Hp++hsVxbQ4BYO7hU=
 filippo.io/edwards25519 v1.1.0 h1:FNf4tywRC1HmFuKW5xopWpigGjJKiJSV0Cqo0cJWDaA=
 filippo.io/edwards25519 v1.1.0/go.mod h1:BxyFTGdWcka3PhytdK4V28tE5sGfRvvvRV7EaN4VDT4=
-github.com/AfterShip/clickhouse-sql-parser v0.4.4 h1:iLRwjzz1mWmUEf5UNrSYOceQ+PX9SdBJ8Xw0DNrL114=
-github.com/AfterShip/clickhouse-sql-parser v0.4.4/go.mod h1:W0Z82wJWkJxz2RVun/RMwxue3g7ut47Xxl+SFqdJGus=
+github.com/AfterShip/clickhouse-sql-parser v0.4.7 h1:zbdC0UooWLwBvOi5CeyCA42AWm6lMYuBVy6XnMzmF+c=
+github.com/AfterShip/clickhouse-sql-parser v0.4.7/go.mod h1:W0Z82wJWkJxz2RVun/RMwxue3g7ut47Xxl+SFqdJGus=
 github.com/Azure/azure-sdk-for-go v68.0.0+incompatible h1:fcYLmCpyNYRnvJbPerq7U0hS+6+I79yEDJBqVNcqUzU=
 github.com/Azure/azure-sdk-for-go/sdk/azcore v1.16.0 h1:JZg6HRh6W6U4OLl6lk7BZ7BLisIzM9dG1R50zUk9C/M=
 github.com/Azure/azure-sdk-for-go/sdk/azcore v1.16.0/go.mod h1:YL1xnZ6QejvQHWJrX/AvhFl4WW4rqHVoKspWNVwFk0M=
@@ -100,8 +100,6 @@ github.com/Microsoft/go-winio v0.6.2/go.mod h1:yd8OoFMLzJbo9gZq8j5qaps8bJ9aShtEA
 github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU=
 github.com/SigNoz/govaluate v0.0.0-20240203125216-988004ccc7fd h1:Bk43AsDYe0fhkbj57eGXx8H3ZJ4zhmQXBnrW523ktj8=
 github.com/SigNoz/govaluate v0.0.0-20240203125216-988004ccc7fd/go.mod h1:nxRcH/OEdM8QxzH37xkGzomr1O0JpYBRS6pwjsWW6Pc=
-github.com/SigNoz/signoz-otel-collector v0.111.39-beta.1 h1:ZpSNrOZBOH2iCJIPeER5X0mfxOe64yP3JRX7FzBNfwY=
-github.com/SigNoz/signoz-otel-collector v0.111.39-beta.1/go.mod h1:DCu/D+lqhsPNSGS4IMD+4gn7q06TGzOCKazSy+GURVc=
 github.com/SigNoz/signoz-otel-collector v0.111.39 h1:Dl8QqZNAsj2atxP572OzsszPK0XPpd3LLPNPRAUJ5wo=
 github.com/SigNoz/signoz-otel-collector v0.111.39/go.mod h1:DCu/D+lqhsPNSGS4IMD+4gn7q06TGzOCKazSy+GURVc=
 github.com/afex/hystrix-go v0.0.0-20180502004556-fa1af6a1f4f5/go.mod h1:SkGFH1ia65gfNATL8TAiHDNxPzPdmEL5uirI2Uyuz6c=
diff --git a/pkg/variables/clickhouse/transform.go b/pkg/variables/clickhouse/transform.go
index 844d81d7bf..40914dab90 100644
--- a/pkg/variables/clickhouse/transform.go
+++ b/pkg/variables/clickhouse/transform.go
@@ -2,9 +2,11 @@ package clickhouse
 
 import (
 	"fmt"
+	"slices"
 	"strings"
 
 	"github.com/AfterShip/clickhouse-sql-parser/parser"
+	"github.com/SigNoz/signoz/pkg/variables"
 )
 
 // VariableValue represents a variable's assigned value
@@ -23,12 +25,23 @@ type QueryTransformer struct {
 }
 
 // NewQueryTransformer creates a new transformer with the given SQL and variables
-func NewQueryTransformer(sql string, variables []VariableValue) *QueryTransformer {
+func NewQueryTransformer(sql string, vars []VariableValue) *QueryTransformer {
 	varMap := make(map[string]VariableValue)
-	for _, v := range variables {
+	for _, v := range vars {
+		if slices.Contains(variables.ReservedTimeVars, v.Name) {
+			continue
+		}
 		varMap[v.Name] = v
 	}
 
+	for _, v := range variables.ReservedTimeVars {
+		varMap[v] = VariableValue{
+			Name:        v,
+			IsSelectAll: false,
+			FieldType:   "scalar",
+		}
+	}
+
 	// for each variable, replace the `{{variable_name}}`, [[variable_name]], {{ .variable_name }}, {{.variable_name}}
 	// with $variable_name
 	for name := range varMap {
diff --git a/pkg/variables/reserved_vars.go b/pkg/variables/reserved_vars.go
new file mode 100644
index 0000000000..98455ced7d
--- /dev/null
+++ b/pkg/variables/reserved_vars.go
@@ -0,0 +1,14 @@
+package variables
+
+var ReservedTimeVars = []string{
+	"start_timestamp",
+	"end_timestamp",
+	"start_timestamp_ms",
+	"end_timestamp_ms",
+	"SIGNOZ_START_TIME",
+	"SIGNOZ_END_TIME",
+	"start_timestamp_nano",
+	"end_timestamp_nano",
+	"start_datetime",
+	"end_datetime",
+}