Merge pull request #7587 from planetscale/apply-schema-skip-preflight

ApplySchema: -skip_preflight

go/vt/schemamanager/tablet_executor.go

@@ -42,6 +42,7 @@ type TabletExecutor struct {
 	keyspace             string
 	waitReplicasTimeout  time.Duration
 	ddlStrategy          string
+	skipPreflight        bool
 }
 
 // NewTabletExecutor creates a new TabletExecutor instance
@@ -76,6 +77,11 @@ func (exec *TabletExecutor) SetDDLStrategy(ddlStrategy string) error {
 	return nil
 }
 
+// SkipPreflight disables preflight checks
+func (exec *TabletExecutor) SkipPreflight() {
+	exec.skipPreflight = true
+}
+
 // Open opens a connection to the master for every shard.
 func (exec *TabletExecutor) Open(ctx context.Context, keyspace string) error {
 	if !exec.isClosed {
@@ -212,6 +218,9 @@ func (exec *TabletExecutor) detectBigSchemaChanges(ctx context.Context, parsedDD
 }
 
 func (exec *TabletExecutor) preflightSchemaChanges(ctx context.Context, sqls []string) error {
+	if exec.skipPreflight {
+		return nil
+	}
 	_, err := exec.wr.TabletManagerClient().PreflightSchema(ctx, exec.tablets[0], sqls)
 	return err
 }

go/vt/vtctl/vtctl.go

@@ -403,8 +403,8 @@ var commands = []commandGroup{
 				"[-exclude_tables=''] [-include-views] [-skip-no-master] <keyspace name>",
 				"Validates that the master schema from shard 0 matches the schema on all of the other tablets in the keyspace."},
 			{"ApplySchema", commandApplySchema,
-				"[-allow_long_unavailability] [-wait_replicas_timeout=10s] [-ddl_strategy=<ddl_strategy>] {-sql=<sql> || -sql-file=<filename>} <keyspace>",
-				"Applies the schema change to the specified keyspace on every master, running in parallel on all shards. The changes are then propagated to replicas via replication. If -allow_long_unavailability is set, schema changes affecting a large number of rows (and possibly incurring a longer period of unavailability) will not be rejected. ddl_strategy is used to intruct migrations via gh-ost or pt-osc with optional parameters"},
+				"[-allow_long_unavailability] [-wait_replicas_timeout=10s] [-ddl_strategy=<ddl_strategy>] [-skip_preflight] {-sql=<sql> || -sql-file=<filename>} <keyspace>",
+				"Applies the schema change to the specified keyspace on every master, running in parallel on all shards. The changes are then propagated to replicas via replication. If -allow_long_unavailability is set, schema changes affecting a large number of rows (and possibly incurring a longer period of unavailability) will not be rejected. ddl_strategy is used to intruct migrations via gh-ost or pt-osc with optional parameters. If -skip_preflight, SQL goes directly to shards without going through sanity checks"},
 			{"CopySchemaShard", commandCopySchemaShard,
 				"[-tables=<table1>,<table2>,...] [-exclude_tables=<table1>,<table2>,...] [-include-views] [-skip-verify] [-wait_replicas_timeout=10s] {<source keyspace/shard> || <source tablet alias>} <destination keyspace/shard>",
 				"Copies the schema from a source shard's master (or a specific tablet) to a destination shard. The schema is applied directly on the master of the destination shard, and it is propagated to the replicas through binlogs."},
@@ -2853,6 +2853,7 @@ func commandApplySchema(ctx context.Context, wr *wrangler.Wrangler, subFlags *fl
 	sqlFile := subFlags.String("sql-file", "", "Identifies the file that contains the SQL commands")
 	ddlStrategy := subFlags.String("ddl_strategy", string(schema.DDLStrategyDirect), "Online DDL strategy, compatible with @@ddl_strategy session variable (examples: 'gh-ost', 'pt-osc', 'gh-ost --max-load=Threads_running=100'")
 	waitReplicasTimeout := subFlags.Duration("wait_replicas_timeout", wrangler.DefaultWaitReplicasTimeout, "The amount of time to wait for replicas to receive the schema change via replication.")
+	skipPreflight := subFlags.Bool("skip_preflight", false, "Skip pre-apply schema checks, and dircetly forward schema change query to shards")
 	if err := subFlags.Parse(args); err != nil {
 		return err
 	}
@@ -2874,6 +2875,9 @@ func commandApplySchema(ctx context.Context, wr *wrangler.Wrangler, subFlags *fl
 	if *allowLongUnavailability {
 		executor.AllowBigSchemaChange()
 	}
+	if *skipPreflight {
+		executor.SkipPreflight()
+	}
 	if err := executor.SetDDLStrategy(*ddlStrategy); err != nil {
 		return nil
 	}