func buildDeletePlan(del *sqlparser.Delete, schema *Schema) *Plan {
plan := &Plan{
ID: NoPlan,
Rewritten: generateQuery(del),
}
tablename := sqlparser.GetTableName(del.Table)
plan.Table, plan.Reason = schema.FindTable(tablename)
if plan.Reason != "" {
return plan
}
if !plan.Table.Keyspace.Sharded {
plan.ID = DeleteUnsharded
return plan
}
getWhereRouting(del.Where, plan, true)
switch plan.ID {
case SelectEqual:
plan.ID = DeleteEqual
case SelectIN, SelectScatter:
plan.ID = NoPlan
plan.Reason = "too complex"
default:
panic("unexpected")
}
return plan
}
func buildUpdatePlan(upd *sqlparser.Update, schema *Schema) *Plan {
plan := &Plan{
ID: NoPlan,
Rewritten: generateQuery(upd),
}
tablename := sqlparser.GetTableName(upd.Table)
plan.Table, plan.Reason = schema.FindTable(tablename)
if plan.Reason != "" {
return plan
}
if !plan.Table.Keyspace.Sharded {
plan.ID = UpdateUnsharded
return plan
}
getWhereRouting(upd.Where, plan, true)
switch plan.ID {
case SelectEqual:
plan.ID = UpdateEqual
case SelectIN, SelectScatter:
plan.ID = NoPlan
plan.Reason = "too complex"
return plan
default:
panic("unexpected")
}
if isIndexChanging(upd.Exprs, plan.Table.ColVindexes) {
plan.ID = NoPlan
plan.Reason = "index is changing"
}
return plan
}
// Ensure that the input query is a Select statement that contains no Join,
// GroupBy, OrderBy, Limit or Distinct operations. Also ensure that the
// source table is present in the schema and has at least one primary key.
func (qs *QuerySplitter) validateQuery() error {
statement, err := sqlparser.Parse(qs.query.Sql)
if err != nil {
return err
}
var ok bool
qs.sel, ok = statement.(*sqlparser.Select)
if !ok {
return fmt.Errorf("not a select statement")
}
if qs.sel.Distinct != "" || qs.sel.GroupBy != nil ||
qs.sel.Having != nil || len(qs.sel.From) != 1 ||
qs.sel.OrderBy != nil || qs.sel.Limit != nil ||
qs.sel.Lock != "" {
return fmt.Errorf("unsupported query")
}
node, ok := qs.sel.From[0].(*sqlparser.AliasedTableExpr)
if !ok {
return fmt.Errorf("unsupported query")
}
qs.tableName = sqlparser.GetTableName(node.Expr)
if qs.tableName == "" {
return fmt.Errorf("not a simple table expression")
}
tableInfo, ok := qs.schemaInfo.tables[qs.tableName]
if !ok {
return fmt.Errorf("can't find table in schema")
}
if len(tableInfo.PKColumns) == 0 {
return fmt.Errorf("no primary keys")
}
qs.pkCol = tableInfo.GetPKColumn(0).Name
return nil
}
func buildInsertPlan(ins *sqlparser.Insert, schema *Schema) *Plan {
plan := &Plan{
ID: NoPlan,
Rewritten: generateQuery(ins),
}
tablename := sqlparser.GetTableName(ins.Table)
plan.Table, plan.Reason = schema.FindTable(tablename)
if plan.Reason != "" {
return plan
}
if !plan.Table.Keyspace.Sharded {
plan.ID = InsertUnsharded
return plan
}
if len(ins.Columns) == 0 {
plan.Reason = "no column list"
return plan
}
var values sqlparser.Values
switch rows := ins.Rows.(type) {
case *sqlparser.Select, *sqlparser.Union:
plan.Reason = "subqueries not allowed"
return plan
case sqlparser.Values:
values = rows
default:
panic("unexpected")
}
if len(values) != 1 {
plan.Reason = "multi-row inserts not supported"
return plan
}
switch values[0].(type) {
case *sqlparser.Subquery:
plan.Reason = "subqueries not allowed"
return plan
}
row := values[0].(sqlparser.ValTuple)
if len(ins.Columns) != len(row) {
plan.Reason = "column list doesn't match values"
return plan
}
colVindexes := schema.Tables[tablename].ColVindexes
plan.ID = InsertSharded
plan.Values = make([]interface{}, 0, len(colVindexes))
for _, index := range colVindexes {
if err := buildIndexPlan(ins, tablename, index, plan); err != nil {
plan.ID = NoPlan
plan.Reason = err.Error()
return plan
}
}
plan.Rewritten = generateQuery(ins)
return plan
}
// TODO(sougou): Copied from tabletserver. Reuse.
func analyzeFrom(tableExprs sqlparser.TableExprs) (tablename string, hasHints bool) {
if len(tableExprs) > 1 {
return "", false
}
node, ok := tableExprs[0].(*sqlparser.AliasedTableExpr)
if !ok {
return "", false
}
return sqlparser.GetTableName(node.Expr), node.Hints != nil
}
func analyzeUpdate(upd *sqlparser.Update, getTable TableGetter) (plan *ExecPlan, err error) {
plan = &ExecPlan{
PlanId: PLAN_PASS_DML,
FullQuery: GenerateFullQuery(upd),
}
tableName := sqlparser.GetTableName(upd.Table)
if tableName == "" {
plan.Reason = REASON_TABLE
return plan, nil
}
tableInfo, err := plan.setTableInfo(tableName, getTable)
if err != nil {
return nil, err
}
if len(tableInfo.Indexes) == 0 || tableInfo.Indexes[0].Name != "PRIMARY" {
log.Warningf("no primary key for table %s", tableName)
plan.Reason = REASON_TABLE_NOINDEX
return plan, nil
}
plan.SecondaryPKValues, err = analyzeUpdateExpressions(upd.Exprs, tableInfo.Indexes[0])
if err != nil {
if err == TooComplex {
plan.Reason = REASON_PK_CHANGE
return plan, nil
}
return nil, err
}
plan.OuterQuery = GenerateUpdateOuterQuery(upd)
if conditions := analyzeWhere(upd.Where); conditions != nil {
pkValues, err := getPKValues(conditions, tableInfo.Indexes[0])
if err != nil {
return nil, err
}
if pkValues != nil {
plan.PlanId = PLAN_DML_PK
plan.PKValues = pkValues
return plan, nil
}
}
plan.PlanId = PLAN_DML_SUBQUERY
plan.Subquery = GenerateUpdateSubquery(upd, tableInfo)
return plan, nil
}
func analyzeInsert(ins *sqlparser.Insert, getTable TableGetter) (plan *ExecPlan, err error) {
plan = &ExecPlan{
PlanId: PLAN_PASS_DML,
FullQuery: GenerateFullQuery(ins),
}
tableName := sqlparser.GetTableName(ins.Table)
if tableName == "" {
plan.Reason = REASON_TABLE
return plan, nil
}
tableInfo, err := plan.setTableInfo(tableName, getTable)
if err != nil {
return nil, err
}
if len(tableInfo.Indexes) == 0 || tableInfo.Indexes[0].Name != "PRIMARY" {
log.Warningf("no primary key for table %s", tableName)
plan.Reason = REASON_TABLE_NOINDEX
return plan, nil
}
pkColumnNumbers := getInsertPKColumns(ins.Columns, tableInfo)
if ins.OnDup != nil {
// Upserts are not safe for statement based replication:
// http://bugs.mysql.com/bug.php?id=58637
plan.Reason = REASON_UPSERT
return plan, nil
}
if sel, ok := ins.Rows.(sqlparser.SelectStatement); ok {
plan.PlanId = PLAN_INSERT_SUBQUERY
plan.OuterQuery = GenerateInsertOuterQuery(ins)
plan.Subquery = GenerateSelectLimitQuery(sel)
if len(ins.Columns) != 0 {
plan.ColumnNumbers, err = analyzeSelectExprs(sqlparser.SelectExprs(ins.Columns), tableInfo)
if err != nil {
return nil, err
}
} else {
// StarExpr node will expand into all columns
n := sqlparser.SelectExprs{&sqlparser.StarExpr{}}
plan.ColumnNumbers, err = analyzeSelectExprs(n, tableInfo)
if err != nil {
return nil, err
}
}
plan.SubqueryPKColumns = pkColumnNumbers
return plan, nil
}
// If it's not a sqlparser.SelectStatement, it's Values.
rowList := ins.Rows.(sqlparser.Values)
pkValues, err := getInsertPKValues(pkColumnNumbers, rowList, tableInfo)
if err != nil {
return nil, err
}
if pkValues != nil {
plan.PlanId = PLAN_INSERT_PK
plan.OuterQuery = plan.FullQuery
plan.PKValues = pkValues
}
return plan, nil
}