drainer: Ignore all tidb placement operations (#1141)

close #1140

pkg/loader/util.go

@@ -34,8 +34,9 @@ import (
 
 var (
 	// ErrTableNotExist means the table not exist.
-	ErrTableNotExist   = errors.New("table not exist")
-	defaultTiDBTxnMode = "optimistic"
+	ErrTableNotExist         = errors.New("table not exist")
+	defaultTiDBTxnMode       = "optimistic"
+	defaultTiDBPlacementMode = "ignore"
 )
 
 const (
@@ -133,6 +134,8 @@ func createDBWitSessions(dsn string, params map[string]string) (db *gosql.DB, er
 		// default is false, must enable for insert value explicit, or can't replicate.
 		"allow_auto_random_explicit_insert": "1",
 		"tidb_txn_mode":                     defaultTiDBTxnMode,
+		// ignore all placement settings
+		"tidb_placement_mode": defaultTiDBPlacementMode,
 	}
 	var tryDB *gosql.DB
 	tryDB, err = gosql.Open("mysql", dsn)
@@ -164,6 +167,9 @@ func createDBWitSessions(dsn string, params map[string]string) (db *gosql.DB, er
 	}
 
 	for k, v := range support {
+		// The value should be quoted and then query escaped
+		// see: https://github.com/go-sql-driver/mysql#system-variables
+		v = fmt.Sprintf("'%s'", v)
 		dsn += fmt.Sprintf("&%s=%s", k, url.QueryEscape(v))
 	}
 

tests/placement_rules/run.sh

@@ -13,10 +13,12 @@ run_sql 'CREATE PLACEMENT POLICY x1 FOLLOWERS=4'
 run_sql 'CREATE TABLE placement_test.t1 (a INT NOT NULL PRIMARY KEY, b VARCHAR(100)) PLACEMENT POLICY=x1;'
 run_sql "INSERT INTO placement_test.t1 (a,b) VALUES(1,'a'),(2,'b'),(3,'c'),(4,'d');"
 run_sql "INSERT INTO placement_test.t1 (a,b) VALUES(5,'e'),(6,'f'),(7,'g'),(8,'h');"
-down_run_sql 'CREATE PLACEMENT POLICY x1 FOLLOWERS=4'
 
 sleep 3
 
+down_run_sql 'SHOW PLACEMENT'
+check_not_contains 'Target: POLICY x1'
+check_not_contains 'Target: TABLE placement_test.t1'
 down_run_sql 'SELECT a, b FROM placement_test.t1 order by a'
 check_contains 'a: 7'
 check_contains 'b: g'