// split splits the query into multiple queries. validateQuery() must return
// nil error before split() is called.
func (qs *QuerySplitter) split(pkMinMax *mproto.QueryResult) []proto.QuerySplit {
boundaries := qs.getSplitBoundaries(pkMinMax)
splits := []proto.QuerySplit{}
// No splits, return the original query as a single split
if len(boundaries) == 0 {
split := &proto.QuerySplit{
Query: *qs.query,
}
splits = append(splits, *split)
} else {
// Loop through the boundaries and generated modified where clauses
start := sqltypes.Value{}
clauses := []*sqlparser.Where{}
for _, end := range boundaries {
clauses = append(clauses, qs.getWhereClause(start, end))
start.Inner = end.Inner
}
clauses = append(clauses, qs.getWhereClause(start, sqltypes.Value{}))
// Generate one split per clause
for _, clause := range clauses {
sel := qs.sel
sel.Where = clause
q := &proto.BoundQuery{
Sql: sqlparser.String(sel),
BindVariables: qs.query.BindVariables,
}
split := &proto.QuerySplit{
Query: *q,
RowCount: qs.rowCount,
}
splits = append(splits, *split)
}
}
return splits
}
// split splits the query into multiple queries. validateQuery() must return
// nil error before split() is called.
func (qs *QuerySplitter) split(columnType int64, pkMinMax *mproto.QueryResult) ([]proto.QuerySplit, error) {
boundaries, err := qs.splitBoundaries(columnType, pkMinMax)
if err != nil {
return nil, err
}
splits := []proto.QuerySplit{}
// No splits, return the original query as a single split
if len(boundaries) == 0 {
split := &proto.QuerySplit{
Query: *qs.query,
}
splits = append(splits, *split)
} else {
boundaries = append(boundaries, sqltypes.Value{})
whereClause := qs.sel.Where
// Loop through the boundaries and generated modified where clauses
start := sqltypes.Value{}
for _, end := range boundaries {
bindVars := make(map[string]interface{}, len(qs.query.BindVariables))
for k, v := range qs.query.BindVariables {
bindVars[k] = v
}
qs.sel.Where = qs.getWhereClause(whereClause, bindVars, start, end)
q := &proto.BoundQuery{
Sql: sqlparser.String(qs.sel),
BindVariables: bindVars,
}
split := &proto.QuerySplit{
Query: *q,
RowCount: qs.rowCount,
}
splits = append(splits, *split)
start.Inner = end.Inner
}
qs.sel.Where = whereClause // reset where clause
}
return splits, err
}