rewrite support regexp replace

	add reg2select, for oracle, sql server and other dbms

Makefile

@@ -143,24 +143,6 @@ heuristic: doc
 	go test github.com/XiaoMi/soar/advisor -v -update -run TestMergeConflictHeuristicRules
 	docker stop soar-mysql 2>/dev/null || true
 
-# Update vitess vendor
-.PHONY: vitess
-vitess:
-	@echo "$(CGREEN)Update vitess deps ...$(CEND)"
-	govendor fetch -v vitess.io/vitess/...
-
-# Update tidb vendor
-.PHONY: tidb
-tidb:
-	@echo "$(CGREEN)Update tidb deps ...$(CEND)"
-	govendor fetch -v github.com/pingcap/tidb/...
-
-# make pingcap parser
-.PHONY: pingcap-parser
-pingcap-parser: tidb
-	@echo "$(CGREEN)Update pingcap parser deps ...$(CEND)"
-	govendor fetch -v github.com/pingcap/parser/...
-
 # Update all vendor
 .PHONY: vendor
 vendor: vitess pingcap-parser

ast/rewrite.go

@@ -52,6 +52,13 @@ func init() {
 			Suggest:     "select * from film where length > 100",
 			Func:        (*Rewrite).RewriteDML2Select,
 		},
+		{
+			Name:        "reg2select",
+			Description: "使用正则的方式将数据库更新请求转换为只读查询请求，便于执行EXPLAIN",
+			Original:    "DELETE FROM film WHERE length > 100",
+			Suggest:     "select * from film where length > 100",
+			Func:        (*Rewrite).RewriteReg2Select,
+		},
 		{
 			Name:        "star2columns",
 			Description: "为SELECT *补全表的列信息",
@@ -1619,6 +1626,24 @@ func (rw *Rewrite) RewriteDML2Select() *Rewrite {
 	return rw
 }
 
+func (rw *Rewrite) RewriteReg2Select() *Rewrite {
+	var pre = 9
+	if len(rw.SQL) < pre {
+		// SQL to short no need convert
+		return rw
+	}
+	if strings.HasPrefix(strings.ToLower(rw.SQL[:pre]), "select") {
+		rw.NewSQL = rw.SQL
+	}
+	if strings.HasPrefix(strings.ToLower(rw.SQL[:pre]), "update") {
+		rw.NewSQL = regUpdate2Select(rw.SQL)
+	}
+	if strings.HasPrefix(strings.ToLower(rw.SQL[:pre]), "delete") {
+		rw.NewSQL = regDelete2Select(rw.SQL)
+	}
+	return rw
+}
+
 // delete2Select 将 Delete 语句改写成 Select
 func delete2Select(stmt *sqlparser.Delete) string {
 	newSQL := &sqlparser.Select{
@@ -1632,6 +1657,17 @@ func delete2Select(stmt *sqlparser.Delete) string {
 	return sqlparser.String(newSQL)
 }
 
+// regDelete2Select convert delete to select by regexp
+func regDelete2Select(sql string) string {
+	sql = strings.TrimSpace(sql)
+	sqlRegexp := regexp.MustCompile(`^(?i)delete\s+from\s+(.*)$`)
+	params := sqlRegexp.FindStringSubmatch(sql)
+	if len(params) > 1 {
+		return fmt.Sprintf(`select * from %s`, params[1])
+	}
+	return sql
+}
+
 // update2Select 将 Update 语句改写成 Select
 func update2Select(stmt *sqlparser.Update) string {
 	newSQL := &sqlparser.Select{
@@ -1646,6 +1682,17 @@ func update2Select(stmt *sqlparser.Update) string {
 	return sqlparser.String(newSQL)
 }
 
+// regUpdate2Select convert update to select by regexp
+func regUpdate2Select(sql string) string {
+	sql = strings.TrimSpace(sql)
+	sqlRegexp := regexp.MustCompile(`^(?i)update\s+(.*)\s+set\s+(.*)\s+(where\s+.*)$`)
+	params := sqlRegexp.FindStringSubmatch(sql)
+	if len(params) > 2 {
+		return fmt.Sprintf(`select * from %s %s`, params[1], params[3])
+	}
+	return sql
+}
+
 // insert2Select 将 Insert 语句改写成 Select
 func insert2Select(stmt *sqlparser.Insert) string {
 	switch row := stmt.Rows.(type) {

ast/rewrite_test.go

@@ -587,6 +587,31 @@ func TestRewriteDML2Select(t *testing.T) {
 	common.Log.Debug("Exiting function: %s", common.GetFunctionName())
 }
 
+func TestRewriteReg2Select(t *testing.T) {
+	common.Log.Debug("Entering function: %s", common.GetFunctionName())
+	testSQL := []map[string]string{
+		{
+			"input":  "select 1 from dual",
+			"output": "select 1 from dual",
+		},
+		{
+			"input":  "delete from dual",
+			"output": "select * from dual",
+		},
+		{
+			"input":  "update tb set col = 1 where col = 2",
+			"output": "select * from tb where col = 2",
+		},
+	}
+	for _, sql := range testSQL {
+		rw := NewRewrite(sql["input"]).RewriteReg2Select()
+		if rw.NewSQL != sql["output"] {
+			t.Errorf("want: %s\ngot: %s", sql["output"], rw.NewSQL)
+		}
+	}
+	common.Log.Debug("Exiting function: %s", common.GetFunctionName())
+}
+
 func TestRewriteDistinctStar(t *testing.T) {
 	common.Log.Debug("Entering function: %s", common.GetFunctionName())
 	testSQL := []map[string]string{

ast/testdata/TestListRewriteRules.golden

@@ -13,6 +13,20 @@ DELETE FROM film WHERE length > 100
 
 * **Suggest**:
 
+```sql
+select * from film where length > 100
+```
+## reg2select
+* **Description**:使用正则的方式将数据库更新请求转换为只读查询请求，便于执行EXPLAIN
+
+* **Original**:
+
+```sql
+DELETE FROM film WHERE length > 100
+```
+
+* **Suggest**:
+
 ```sql
 select * from film where length > 100
 ```
@@ -277,6 +291,12 @@ use sakila;
     "Original": "DELETE FROM film WHERE length \u003e 100",
     "Suggest": "select * from film where length \u003e 100"
   },
+  {
+    "Name": "reg2select",
+    "Description": "使用正则的方式将数据库更新请求转换为只读查询请求，便于执行EXPLAIN",
+    "Original": "DELETE FROM film WHERE length \u003e 100",
+    "Suggest": "select * from film where length \u003e 100"
+  },
   {
     "Name": "star2columns",
     "Description": "为SELECT *补全表的列信息",

deps.sh

 #!/bin/bash
 
-NEEDED_COMMANDS="docker git go govendor retool bats"
+NEEDED_COMMANDS="docker git go retool bats"
 
 for cmd in ${NEEDED_COMMANDS} ; do
     if ! command -v "${cmd}" &> /dev/null ; then