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1 | 1 | #execplan |
2 | | -PostgreSQLExtension for raw query plan execution |
| 2 | +PostgreSQLpatch & extension for raw query plan execution |
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4 | | -This project dedicated toparallelquery execution problem. |
| 4 | +This project dedicated to query execution problem in DBMS for computing systems with cluster architecture. |
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6 | | -Parallel DBMS needs to execute an identical query plan at each computing node. It is needed for tuples redistribution during a query. |
7 | | -Today PostgreSQL can process only SQL strings. But it is not guaranteed, that the planner at each node will construct same query plan, because different statistics, relation sizes e.t.c. |
| 6 | +The DBMS may need to execute an identical query plan at each computing node. |
| 7 | +Today PostgreSQL can process only SQL statements. But it is not guaranteed, that the planner at each node will construct same query plan, because different statistics, relation sizes e.t.c. |
| 8 | + |
| 9 | +This solution based on postgres-xl approach: plan tree is serialized by the nodeToString() routine. |
| 10 | +Further, the serialized plan transfer by new libpq routine called`PQsendPlan`. |
| 11 | +In this project we use postgres_fdw connections for management of sessions and remote transactions. |
| 12 | +Some`repeater` extension used for the demonstration of plan transfer machinery. |