// SplitQuery splits a BoundQuery into smaller queries that return a subset of rows from the original query.
func (sq *SqlQuery) SplitQuery(context context.Context, req *proto.SplitQueryRequest, reply *proto.SplitQueryResult) error {
logStats := newSqlQueryStats("SplitQuery", context)
var err error
// TODO(sougou/anandhenry): Add session validation.
defer handleError(&err, logStats)
splitter := NewQuerySplitter(&(req.Query), req.SplitCount, sq.qe.schemaInfo)
err = splitter.validateQuery()
if err != nil {
return NewTabletError(FAIL, "query validation error: %s", err)
}
// Partial initialization or QueryExecutor is enough to call execSQL
requestContext := RequestContext{
ctx: context,
logStats: logStats,
qe: sq.qe,
}
conn := getOrPanic(sq.qe.connPool)
// TODO: For fetching pkMinMax, include where clauses on the
// primary key, if any, in the original query which might give a narrower
// range of PKs to work with.
minMaxSql := fmt.Sprintf("SELECT MIN(%v), MAX(%v) FROM %v", splitter.pkCol, splitter.pkCol, splitter.tableName)
pkMinMax := requestContext.execSQL(conn, minMaxSql, true)
reply.Queries = splitter.split(pkMinMax)
return nil
}
// SplitQuery is part of the queryservice.QueryService interface
func (f *FakeQueryService) SplitQuery(ctx context.Context, req *proto.SplitQueryRequest, reply *proto.SplitQueryResult) error {
if f.hasError {
return testTabletError
}
if f.panics {
panic(fmt.Errorf("test-triggered panic"))
}
if !reflect.DeepEqual(req.Query, splitQueryBoundQuery) {
f.t.Errorf("invalid SplitQuery.SplitQueryRequest.Query: got %v expected %v", req.Query, splitQueryBoundQuery)
}
if req.SplitCount != splitQuerySplitCount {
f.t.Errorf("invalid SplitQuery.SplitQueryRequest.SplitCount: got %v expected %v", req.SplitCount, splitQuerySplitCount)
}
reply.Queries = splitQueryQuerySplitList
return nil
}
// SplitQuery is part of the queryservice.QueryService interface
func (f *FakeQueryService) SplitQuery(ctx context.Context, target *pb.Target, req *proto.SplitQueryRequest, reply *proto.SplitQueryResult) error {
if f.panics {
panic(fmt.Errorf("test-triggered panic"))
}
if f.checkExtraFields {
f.checkTargetCallerID(ctx, "SplitQuery", target)
}
if !reflect.DeepEqual(req.Query, splitQueryBoundQuery) {
f.t.Errorf("invalid SplitQuery.SplitQueryRequest.Query: got %v expected %v", req.Query, splitQueryBoundQuery)
}
if req.SplitColumn != splitQuerySplitColumn {
f.t.Errorf("invalid SplitQuery.SplitQueryRequest.SplitColumn: got %v expected %v", req.SplitColumn, splitQuerySplitColumn)
}
if req.SplitCount != splitQuerySplitCount {
f.t.Errorf("invalid SplitQuery.SplitQueryRequest.SplitCount: got %v expected %v", req.SplitCount, splitQuerySplitCount)
}
reply.Queries = splitQueryQuerySplitList
return nil
}
// AddTabletErrorToSplitQueryResult will mutate a SplitQueryResult struct to fill in the Err
// field with details from the TabletError.
func AddTabletErrorToSplitQueryResult(err error, reply *proto.SplitQueryResult) {
if err == nil {
return
}
reply.Err = rpcErrFromTabletError(err)
}