// StreamExecute executes the query and streams its result.
// The first QueryResult will have Fields set (and Rows nil)
// The subsequent QueryResult will have Rows set (and Fields nil)
func (qe *QueryEngine) StreamExecute(logStats *SQLQueryStats, query *proto.Query, sendReply func(*mproto.QueryResult) error) {
if query.BindVariables == nil { // will help us avoid repeated nil checks
query.BindVariables = make(map[string]interface{})
}
logStats.BindVariables = query.BindVariables
// cheap hack: strip trailing comment into a special bind var
stripTrailing(query)
plan := qe.schemaInfo.GetStreamPlan(query.Sql)
logStats.PlanType = "SELECT_STREAM"
logStats.OriginalSql = query.Sql
defer queryStats.Record("SELECT_STREAM", time.Now())
authorized := tableacl.Authorized(plan.TableName, plan.PlanId.MinRole())
qe.checkTableAcl(plan.TableName, plan.PlanId, authorized, logStats.context.GetUsername())
// does the real work: first get a connection
waitingForConnectionStart := time.Now()
conn := getOrPanic(qe.streamConnPool)
logStats.WaitingForConnection += time.Now().Sub(waitingForConnectionStart)
defer conn.Recycle()
qd := NewQueryDetail(query, logStats.context, conn.Id())
qe.streamQList.Add(qd)
defer qe.streamQList.Remove(qd)
// then let's stream! Wrap callback function to return an
// error on query termination to stop further streaming
qe.fullStreamFetch(logStats, conn, plan.FullQuery, query.BindVariables, nil, nil, sendReply)
}
func checkAccess(configData []byte, tableName string, role tableacl.Role, t *testing.T, want bool) {
checkLoad(configData, true, t)
got := tableacl.Authorized(tableName, role).IsMember(currentUser())
if want != got {
t.Errorf("got %v, want %v", got, want)
}
}
// GetPlan returns the ExecPlan that for the query. Plans are cached in a cache.LRUCache.
func (si *SchemaInfo) GetPlan(ctx context.Context, logStats *LogStats, sql string) *ExecPlan {
span := trace.NewSpanFromContext(ctx)
span.StartLocal("SchemaInfo.GetPlan")
defer span.Finish()
// Fastpath if plan already exists.
if plan := si.getQuery(sql); plan != nil {
return plan
}
// TODO(sougou): It's not correct to hold this lock here because the code
// below runs queries against MySQL. But if we don't hold the lock, there
// are other race conditions where identical queries will end up building
// plans and compete with populating the query cache. In other words, we
// need a more elaborate scheme that blocks less, but still prevents these
// race conditions.
si.mu.Lock()
defer si.mu.Unlock()
// Recheck. A plan might have been built by someone else.
if plan := si.getQuery(sql); plan != nil {
return plan
}
var tableInfo *TableInfo
GetTable := func(tableName string) (table *schema.Table, ok bool) {
tableInfo, ok = si.tables[tableName]
if !ok {
return nil, false
}
return tableInfo.Table, true
}
splan, err := planbuilder.GetExecPlan(sql, GetTable)
if err != nil {
panic(PrefixTabletError(vtrpcpb.ErrorCode_UNKNOWN_ERROR, err, ""))
}
plan := &ExecPlan{ExecPlan: splan, TableInfo: tableInfo}
plan.Rules = si.queryRuleSources.filterByPlan(sql, plan.PlanID, plan.TableName)
plan.Authorized = tableacl.Authorized(plan.TableName, plan.PlanID.MinRole())
if plan.PlanID.IsSelect() {
if plan.FieldQuery == nil {
log.Warningf("Cannot cache field info: %s", sql)
} else {
conn := getOrPanic(ctx, si.connPool)
defer conn.Recycle()
sql := plan.FieldQuery.Query
start := time.Now()
r, err := conn.Exec(ctx, sql, 1, true)
logStats.AddRewrittenSQL(sql, start)
if err != nil {
panic(PrefixTabletError(vtrpcpb.ErrorCode_UNKNOWN_ERROR, err, "Error fetching fields: "))
}
plan.Fields = r.Fields
}
} else if plan.PlanID == planbuilder.PlanDDL || plan.PlanID == planbuilder.PlanSet {
return plan
}
si.queries.Set(sql, plan)
return plan
}
func checkAccess(config *tableaclpb.Config, tableName string, role tableacl.Role, want bool) error {
if err := checkLoad(config, true); err != nil {
return err
}
got := tableacl.Authorized(tableName, role).IsMember(currentUser())
if want != got {
return fmt.Errorf("got %v, want %v", got, want)
}
return nil
}
func (si *SchemaInfo) GetPlan(logStats *SQLQueryStats, sql string) (plan *ExecPlan) {
// Fastpath if plan already exists.
if plan := si.getQuery(sql); plan != nil {
return plan
}
si.mu.Lock()
defer si.mu.Unlock()
// Recheck. A plan might have been built by someone else.
if plan := si.getQuery(sql); plan != nil {
return plan
}
var tableInfo *TableInfo
GetTable := func(tableName string) (table *schema.Table, ok bool) {
tableInfo, ok = si.tables[tableName]
if !ok {
return nil, false
}
return tableInfo.Table, true
}
splan, err := planbuilder.GetExecPlan(sql, GetTable)
if err != nil {
panic(NewTabletError(FAIL, "%s", err))
}
plan = &ExecPlan{ExecPlan: splan, TableInfo: tableInfo}
plan.Rules = si.rules.filterByPlan(sql, plan.PlanId, plan.TableName)
plan.Authorized = tableacl.Authorized(plan.TableName, plan.PlanId.MinRole())
if plan.PlanId.IsSelect() {
if plan.FieldQuery == nil {
log.Warningf("Cannot cache field info: %s", sql)
} else {
conn := getOrPanic(si.connPool)
defer conn.Recycle()
sql := plan.FieldQuery.Query
r, err := conn.ExecuteFetch(sql, 1, true)
logStats.QuerySources |= QUERY_SOURCE_MYSQL
logStats.NumberOfQueries += 1
logStats.AddRewrittenSql(sql)
if err != nil {
panic(NewTabletError(FAIL, "Error fetching fields: %v", err))
}
plan.Fields = r.Fields
}
} else if plan.PlanId == planbuilder.PLAN_DDL || plan.PlanId == planbuilder.PLAN_SET {
return plan
}
si.queries.Set(sql, plan)
return plan
}
// GetPlan returns the ExecPlan that for the query. Plans are cached in a cache.LRUCache.
func (si *SchemaInfo) GetPlan(ctx context.Context, logStats *SQLQueryStats, sql string) *ExecPlan {
// Fastpath if plan already exists.
if plan := si.getQuery(sql); plan != nil {
return plan
}
si.mu.Lock()
defer si.mu.Unlock()
// Recheck. A plan might have been built by someone else.
if plan := si.getQuery(sql); plan != nil {
return plan
}
var tableInfo *TableInfo
GetTable := func(tableName string) (table *schema.Table, ok bool) {
tableInfo, ok = si.tables[tableName]
if !ok {
return nil, false
}
return tableInfo.Table, true
}
splan, err := planbuilder.GetExecPlan(sql, GetTable)
if err != nil {
panic(PrefixTabletError(ErrFail, vtrpc.ErrorCode_UNKNOWN_ERROR, err, ""))
}
plan := &ExecPlan{ExecPlan: splan, TableInfo: tableInfo}
plan.Rules = QueryRuleSources.filterByPlan(sql, plan.PlanId, plan.TableName)
plan.Authorized = tableacl.Authorized(plan.TableName, plan.PlanId.MinRole())
if plan.PlanId.IsSelect() {
if plan.FieldQuery == nil {
log.Warningf("Cannot cache field info: %s", sql)
} else {
conn := getOrPanic(ctx, si.connPool)
defer conn.Recycle()
sql := plan.FieldQuery.Query
start := time.Now()
r, err := conn.Exec(ctx, sql, 1, true)
logStats.AddRewrittenSql(sql, start)
if err != nil {
panic(PrefixTabletError(ErrFail, vtrpc.ErrorCode_UNKNOWN_ERROR, err, "Error fetching fields: "))
}
plan.Fields = r.Fields
}
} else if plan.PlanId == planbuilder.PLAN_DDL || plan.PlanId == planbuilder.PLAN_SET {
return plan
}
si.queries.Set(sql, plan)
return plan
}
// GetStreamPlan is similar to GetPlan, but doesn't use the cache
// and doesn't enforce a limit. It just returns the parsed query.
func (si *SchemaInfo) GetStreamPlan(sql string) *ExecPlan {
var tableInfo *TableInfo
GetTable := func(tableName string) (table *schema.Table, ok bool) {
si.mu.Lock()
defer si.mu.Unlock()
tableInfo, ok = si.tables[tableName]
if !ok {
return nil, false
}
return tableInfo.Table, true
}
splan, err := planbuilder.GetStreamExecPlan(sql, GetTable)
if err != nil {
panic(PrefixTabletError(ErrFail, vtrpc.ErrorCode_UNKNOWN_ERROR, err, ""))
}
plan := &ExecPlan{ExecPlan: splan, TableInfo: tableInfo}
plan.Rules = si.queryRuleSources.filterByPlan(sql, plan.PlanId, plan.TableName)
plan.Authorized = tableacl.Authorized(plan.TableName, plan.PlanId.MinRole())
return plan
}
// GetStreamPlan is similar to GetPlan, but doesn't use the cache
// and doesn't enforce a limit. It just returns the parsed query.
func (si *SchemaInfo) GetStreamPlan(sql string) *ExecPlan {
var tableInfo *TableInfo
GetTable := func(tableName string) (table *schema.Table, ok bool) {
si.mu.Lock()
defer si.mu.Unlock()
tableInfo, ok = si.tables[tableName]
if !ok {
return nil, false
}
return tableInfo.Table, true
}
splan, err := planbuilder.GetStreamExecPlan(sql, GetTable)
if err != nil {
panic(NewTabletError(FAIL, "%s", err))
}
plan := &ExecPlan{ExecPlan: splan, TableInfo: tableInfo}
plan.Rules = si.rules.filterByPlan(sql, plan.PlanId, plan.TableName)
plan.Authorized = tableacl.Authorized(plan.TableName, plan.PlanId.MinRole())
return plan
}