Merge pull request #146249 from rharding6373/blathers/backport-release-25.2-146019

release-25.2: changefeedccl: disable unsafe sql updates in nemeses test

Author: rharding6373

pkg/ccl/changefeedccl/cdctest/nemeses.go

@@ -375,29 +375,36 @@ func RunNemesis(
 	// Initialize table rows by repeatedly running the `openTxn` transition,
 	// then randomly either committing or rolling back transactions. This will
 	// leave some committed rows.
-	for i := 0; i < ns.rowCount*5; i++ {
-		payload, err := newOpenTxnPayload(ns)
-		if err != nil {
-			return nil, err
-		}
-		if err := openTxn(fsm.Args{Ctx: ctx, Extended: ns, Payload: payload}); err != nil {
-			return nil, err
-		}
-		// Randomly commit or rollback, but commit at least one row to the table.
-		if rand.Intn(3) < 2 || i == 0 {
-			if err := commit(fsm.Args{Ctx: ctx, Extended: ns}); err != nil {
+	// If sql smith is enabled, we'll insert rows below instead.
+	if !nOp.EnableSQLSmith {
+		for i := 0; i < ns.rowCount*5; i++ {
+			payload, err := newOpenTxnPayload(ns)
+			if err != nil {
 				return nil, err
 			}
-		} else {
-			if err := rollback(fsm.Args{Ctx: ctx, Extended: ns}); err != nil {
+			if err := openTxn(fsm.Args{Ctx: ctx, Extended: ns, Payload: payload}); err != nil {
 				return nil, err
 			}
+			// Randomly commit or rollback, but commit at least one row to the table.
+			if rand.Intn(3) < 2 || i == 0 {
+				if err := commit(fsm.Args{Ctx: ctx, Extended: ns}); err != nil {
+					return nil, err
+				}
+			} else {
+				if err := rollback(fsm.Args{Ctx: ctx, Extended: ns}); err != nil {
+					return nil, err
+				}
+			}
 		}
 	}
 
 	if nOp.EnableSQLSmith {
+		// Some unsafe queries can hang, so avoid them.
+		if _, err := db.Exec("SET sql_safe_updates=true"); err != nil {
+			return nil, err
+		}
 		queryGen, _ := sqlsmith.NewSmither(db, rng,
-			sqlsmith.MutationsOnly(),
+			sqlsmith.InsUpdDelOnly(),
 			sqlsmith.SetScalarComplexity(0.5),
 			sqlsmith.SetComplexity(0.1),
 			// TODO(#129072): Reenable cross joins when the likelihood of generating
@@ -408,6 +415,7 @@ func RunNemesis(
 			// supported under the serializable isolation.
 			sqlsmith.DisableIsolationChange(),
 		)
+
 		defer queryGen.Close()
 		const numInserts = 100
 		time := timeutil.Now()
@@ -422,6 +430,28 @@ func RunNemesis(
 				continue
 			}
 		}
+		// Reenable unsafe queries, since the test sometimes alters tables.
+		if _, err := db.Exec("SET sql_safe_updates=false"); err != nil {
+			return nil, err
+		}
+	}
+
+	// Print the contents of the table in a way that can be reproduced.
+	rows, err := db.Query("SELECT * FROM foo")
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	// Iterate over the rows and print them
+	for rows.Next() {
+		var id int
+		var ts string
+		if err := rows.Scan(&id, &ts); err != nil {
+			log.Infof(ctx, "# skipping row because error: %s", err)
+			continue
+		}
+		log.Infof(ctx, "INSERT INTO foo (id,ts) VALUES (%d, %s);", id, ts)
 	}
 
 	cfo := newChangefeedOption(testName)

pkg/internal/sqlsmith/sqlsmith.go

@@ -470,6 +470,17 @@ var InsUpdOnly = simpleOption("inserts and updates only", func(s *Smither) {
 	}
 })
 
+// InsUpdDelOnly causes the Smither to emit 80% INSERT, 10% UPDATE,
+// 10% DELETE statements.
+var InsUpdDelOnly = simpleOption("inserts updates and deletes only",
+	func(s *Smither) {
+		s.stmtWeights = []statementWeight{
+			{8, makeInsert},
+			{1, makeUpdate},
+			{1, makeDelete},
+		}
+	})
+
 // IgnoreFNs causes the Smither to ignore functions that match the regex.
 func IgnoreFNs(regex string) SmitherOption {
 	r := regexp.MustCompile(regex)