17.05 - Example: Bulk Insert - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Data Manipulation Language

Product
Advanced SQL Engine
Teradata Database
Release Number
17.05
Release Date
January 2021
Content Type
Programming Reference
Publication ID
B035-1146-175K
Language
English (United States)

This INSERT operation performs a bulk insert. With partition level locking, the parser generates a static partition elimination list based on condition "PC = 4" (that is, positional matching of slppit1.pc = srct1.b = 4) and uses this list to place a PartitionRange lock.

The table definitions for this example are as follows:

CREATE TABLE HLSDS.SLPPIT1 (PI  INT, PC INT, X INT) PRIMARY INDEX (PI)
    PARTITION BY (RANGE_N(PC BETWEEN 1 AND 100 EACH 10));
CREATE TABLE HLSDS.SRCT1 (A INT, B INT, C INT) PRIMARY INDEX (A);

An EXPLAIN of the INSERT operation shows the condition PC=4 as WHERE B=4:

  Explain INSERT INTO HLSDS.SLPPIT1 SELECT A, B, C FROM HLSDS.SRCT1
  WHERE B = 4;
  1) First, we lock HLSDS.srct1 for read on a reserved RowHash 
      to prevent global deadlock.
  2) Next, we lock HLSDS.slppit1 for write on a reserved RowHash 
      in a single partition to prevent global deadlock.
  3) We lock HLSDS.srct1 for read, and we lock HLSDS.slppit1
      for write on a single partition.
  4) We do an all-AMPs RETRIEVE step from HLSDS.srct1 by way of 
      an all-rows scan with a condition of ("HLSDS.srct1.b = 4") into
      Spool 1(all_amps), which is built locally on the AMPs.  
      Then we do a SORT to partition Spool 1 by rowkey.
      The size of Spool 1 is estimated
      with no confidence to be 1 row (25 bytes).
      The estimated time for this step is 0.03 seconds.
  5) We do an all-AMPs MERGE into HLSDS.slppit1 from Spool 1
     (Last Use). The size is estimated with no confidence 
      to be 1 row.  The estimated time for this step is 0.55 seconds.
  6) Finally, we send out an END TRANSACTION step to all AMPs 
      involved in processing the request.