The PREVIEW SQL syntax is used to preview SQL execution plan.
PreviewSql ::=
'PREVIEW' sqlStatement
| Column | Description |
|---|---|
| data_source_name | storage unit name |
| actual_sql | actual excute SQL statement |
SQL execution planPREVIEW SELECT * FROM t_order;
mysql> PREVIEW SELECT * FROM t_order;
+------------------+-----------------------+
| data_source_name | actual_sql |
+------------------+-----------------------+
| su_1 | SELECT * FROM t_order |
+------------------+-----------------------+
1 row in set (0.18 sec)
PREVIEW