Thread: Table Partitioning

On Tue, May 21, 2013 at 11:03 PM, Richard Onorato <richard_onorato@yahoo.com> wrote:

I am wanting to partition my data based on a mod of one of the bigint columns, but when I run my insert test all the data goes into the base table and not the partitions.  Here is what the table looks like:

CREATE table MyMappingTable ( id bigserial NOT NULL,

                                     c1 bigInt NOT NULL,

                                     c2 bigInt NOT NULL,

                                     c3 bigint NOT NULL,

                                     count bigint DEFAULT 1,

                                     createdTime timestamp with time zone default CURRENT_TIMESTAMP,

                                     CONSTRAINT MyMappingTable_index PRIMARY KEY (id) )

with (OIDS=FALSE);

CREATE TABLE MyMappingTableT1 (PRIMARY KEY (id), CHECK((c1 % 5) = 0)) INHERITS (MyMappingTable);

CREATE TABLE MyMappingTableT2 (PRIMARY KEY (id), CHECK((c1 % 5) = 1)) INHERITS (MyMappingTable);

CREATE TABLE MyMappingTableT3 (PRIMARY KEY (id), CHECK((c1 % 5) = 2)) INHERITS (MyMappingTable);

CREATE TABLE MyMappingTableT4 (PRIMARY KEY (id), CHECK((c1 % 5) = 3)) INHERITS (MyMappingTable);

CREATE TABLE MyMappingTableT5 (PRIMARY KEY (id), CHECK((c1 % 5) = 4)) INHERITS (MyMappingTable);

Here is the trigger function that I added to the database:

CREATE OR REPLACE FUNCTION my_mapping_table_insert_trigger()

RETURNS trigger AS $$

BEGIN

  IF ( (NEW.c1 % 5) = 0 ) THEN 

    INSERT INTO MyMappingTableT1 VALUES (NEW.*); 

  ELSIF ( (NEW.c1 % 5) = 1 ) THEN 

    INSERT INTO MyMappingTableT2 VALUES (NEW.*);

  ELSIF ( (NEW.c1 % 5) = 2 ) THEN 

    INSERT INTO MyMappingTableT3 VALUES (NEW.*);

  ELSIF ( (NEW.c1 % 5) = 3 ) THEN 

    INSERT INTO MyMappingTableT4 VALUES (NEW.*);

  ELSIF ( (NEW.c1 % 5) = 4 ) THEN 

    INSERT INTO MyMappingTableT5 VALUES (NEW.*);

  ELSE

    RAISE EXCEPTION 'c1 mod out of range.  Something wrong with the my_mapping_table_insert_trigger() function!';

  END IF;

  RETURN NULL;

END;

$$

LANGUAGE plpgsql;

Here is the Trigger that I added to the table:

CREATE TRIGGER insert_my_mapping_table_trigger 

  BEFORE INSERT ON MyMappingTable 

  FOR EACH ROW EXECUTE PROCEDURE my_mapping_table_insert_trigger();

SET constraint_exclusion = ON;

Regards,

Richard

I tried your test case, its working fine from my end and populating data properly to partition childs. 

insert into mymappingtable values (1,7,20,30,1,now());

insert into mymappingtable values (2,6,20,30,1,now());

insert into mymappingtable values (3,8,20,30,1,now());

insert into mymappingtable values (4,9,20,30,1,now());

insert into mymappingtable values (5,10,20,30,1,now());

postgres=# \dt+ MyMappingTable*

                            List of relations

 Schema |       Name       | Type  |  Owner   |    Size    | Description

--------+------------------+-------+----------+------------+-------------

 public | mymappingtable   | table | postgres | 0 bytes    |

 public | mymappingtablet1 | table | postgres | 8192 bytes |

 public | mymappingtablet2 | table | postgres | 8192 bytes |

 public | mymappingtablet3 | table | postgres | 8192 bytes |

 public | mymappingtablet4 | table | postgres | 8192 bytes |

 public | mymappingtablet5 | table | postgres | 8192 bytes |

---

Regards,

Raghavendra

EnterpriseDB Corporation

Blog: http://raghavt.blogspot.com/