I have the following table(below), and am planning on adding 250 million rows/day, and I'm trying to partition it by date, was wondering how best to do it in Postgres 10, if there is an automatic way to create a partition on daily basis.
CREATE UNLOGGED TABLE public.pricing
(
uitid character varying(40),
batch character varying(32),
scenario character varying(32),
date date NOT NULL,
pv double precision,
ctime real,
CONSTRAINT pricing_pkey PRIMARY KEY (uitid, batch, scenario, date)
)
WITH (
OIDS = FALSE
)
TABLESPACE pg_default;
Related
I am migrating DB from Oracle to PostgreSQL14 ,
Oracle partitioned table was being used which i am trying to migrate to PG.
Below script i am using to create partition with index and tablespace
and getting
ERROR: cannot specify default tablespace for partitioned relations
create table TABLE1
(
COL_DT date constraint N_COL_DT not null
,COL_TM numeric(9) constraint N_COL_TM not null
,COL_INPROC_ID numeric(1) constraint N_COL_INPROC_ID not null
,COL_SUB_ID numeric(7) constraint N_COL_SUB_ID not null
,COL_RECORD_DT date constraint N_COL_RECORD_DT not null
,COL_RECORD_TM numeric(9) constraint N_COL_RECORD_TM not null
,COL_TIMEOFFSET varchar(6) constraint N_COL_TIMEOFFSET not null
,COL_TYPE numeric(1) constraint N_COL_TYPE not null
,COL4 numeric(1) DEFAULT 0 not null
,CONSTRAINT PK_COL primary key (COL_DT,COL_TM,COL_INPROC_ID,COL_SUB_ID) using index tablespace ${TABLESPACE_INDEX}
) partition by range (COL_DT);
CREATE TABLE P_TABLE1_1 PARTITION OF TABLE1 FOR VALUES FROM (MINVALUE) TO (to_date('${PARTITION_DATE_LIMIT}', 'YYYYMM')) partition by list (COL_INPROC_ID);
CREATE TABLE P_TABLE1_1_P0 PARTITION OF P_TABLE1_1 FOR VALUES IN (0) ;
CREATE TABLE P_TABLE1_1_P1 PARTITION OF P_TABLE1_1 FOR VALUES IN (1) ;
CREATE TABLE PMAXVALUE PARTITION OF TABLE1 FOR VALUES FROM (to_date('${PARTITION_DATE_LIMIT}', 'YYYYMM')) TO (MAXVALUE) partition by list (COL_INPROC_ID);
CREATE TABLE PMAXVALUE_P0 PARTITION OF PMAXVALUE FOR VALUES IN (0) ;
CREATE TABLE PMAXVALUE_P1 PARTITION OF PMAXVALUE FOR VALUES IN (1) ;
i am unable to get why this error is coming whereas default tablespace is not used
I ran your statements, and they work like they should, once I substituted constants for the placeholders. However, before v12 it would not have worked the way you want, see the release note entry:
Allow CREATE TABLE's tablespace specification for a partitioned table to affect the tablespace of its children (David Rowley, Álvaro Herrera)
So your problem is not reproducible, but since you are migrating from Oracle, let me give you a piece of advice: don't use tablespaces. They are the bread and butter of Oracle administration, but in PostgreSQL you usually use the default tablespace. There are very few valid reasons to use tablespaces, and particularly in virtualized environments they usually don't make any sense at all. And they make administration (backup etc.) more complicated.
I am migrating DB from Oracle to PostgreSQL14 ,
Oracle partitioned table was being used which i am trying to migrate to PG.
Below script i am using to create partition with index and tablespace
and getting below error
ERROR: unique constraint on partitioned table must include all partitioning columns
In oracle below index was being created on the table which i am now using at partitioned level as i come to know there is limitation , but is there any alternative as this error will cause change in the logic .
Oracle index
CREATE UNIQUE INDEX COL_IDX_ID
ON TABLE1(COL_ID,ERROR_TIME_DT,ERROR_TIME_TM);
Postgres script
create table TABLE1
(
COL_DT date constraint N_COL_DT not null
,COL_TM numeric(9) constraint N_COL_TM not null
,COL_INPROC_ID numeric(1) constraint N_COL_INPROC_ID not null
,COL_SUB_ID numeric(7) constraint N_COL_SUB_ID not null
,COL_RECORD_DT date constraint N_COL_RECORD_DT not null
,COL_RECORD_TM numeric(9) constraint N_COL_RECORD_TM not null
,COL_TIMEOFFSET varchar(6) constraint N_COL_TIMEOFFSET not null
,COL_TYPE numeric(1) constraint N_COL_TYPE not null
,COL4 numeric(1) DEFAULT 0 not null
,ERROR_TIME_DT DATE
,ERROR_TIME_TM numeric(9)
,ERROR__ID numeric(6)
,COL_ID VARCHAR(250)
,CONSTRAINT PK_COL primary key (COL_DT,COL_TM,COL_INPROC_ID,COL_SUB_ID) using index tablespace ${TABLESPACE_INDEX}
) partition by range (COL_DT);
CREATE TABLE P_TABLE1_1 PARTITION OF TABLE1 FOR VALUES FROM (MINVALUE) TO (to_date('${PARTITION_DATE_LIMIT}', 'YYYYMM')) partition by list (COL_INPROC_ID);
CREATE UNIQUE INDEX COL_COLID
ON P_TABLE1_1 ( ERROR_TIME_DT ,ERROR_TIME_TM,COL_ID);
CREATE TABLE P_TABLE1_1_P0 PARTITION OF P_TABLE1_1 FOR VALUES IN (0) ;
CREATE TABLE P_TABLE1_1_P1 PARTITION OF P_TABLE1_1 FOR VALUES IN (1) ;
CREATE TABLE PMAXVALUE PARTITION OF TABLE1 FOR VALUES FROM (to_date('${PARTITION_DATE_LIMIT}', 'YYYYMM')) TO (MAXVALUE) partition by list (COL_INPROC_ID);
CREATE UNIQUE INDEX COL_ID_PMAX
ON PMAXVALUE ( ERROR_TIME_DT ,ERROR_TIME_TM,COL_ID);
CREATE TABLE PMAXVALUE_P0 PARTITION OF PMAXVALUE FOR VALUES IN (0) ;
CREATE TABLE PMAXVALUE_P1 PARTITION OF PMAXVALUE FOR VALUES IN (1) ;
is there any workaround of this problem where i can keep the index same as in oracle "ERROR: unique constraint on partitioned table must include all partitioning columns"
You can only have a unique index on a partitioned table if the partitioning key is part of the index keys. There is no other solution for this, and there is no good workaround either (see below for a small remedy).
Since an index on a partitioned table is always a partitioned index, it can only be UNIQUE if it is by definition, that is, if the partitioning key is an index key. The index partitions can only guarantee uniqueness within the partition itself.
You will have to live without the uniqueness of that index. You can instead define a unique index on each partition, which is almost as good, but does not enforce uniqueness across partitions.
I have a simple table that we use to record debug logs.
There are only 1000 rows in the table.
There are a handful of columns - id (primary), date (indexed), level, a few other small fields and message which could be a large string.
if I query:
select id from public.log
the query completes very quickly (less than 1 second)
if I query:
select id,date from public.log
or
select * from public.log
it takes 1 minute and 28 seconds to complete!
90 Seconds to read 1000 records from a database!
however if I query:
select *
from public.log
where id in (select id from public.log)
it completes in about 1 second.
And here is the CREATE - I just had pgAdmin generate them for me
-- Table: public.inettklog
-- DROP TABLE public.inettklog;
CREATE TABLE public.inettklog
(
id integer NOT NULL DEFAULT nextval('inettklog_id_seq'::regclass),
date timestamp without time zone NOT NULL,
thread character varying(255) COLLATE pg_catalog."default" NOT NULL,
level character varying(20) COLLATE pg_catalog."default" NOT NULL,
logger character varying(255) COLLATE pg_catalog."default" NOT NULL,
customlevel integer,
source character varying(64) COLLATE pg_catalog."default",
logentry json,
CONSTRAINT inettklog_pkey PRIMARY KEY (id)
)
WITH (
OIDS = FALSE
)
TABLESPACE pg_default;
ALTER TABLE public.inettklog
OWNER to postgres;
-- Index: inettklog_ix_logdate
-- DROP INDEX public.inettklog_ix_logdate;
CREATE INDEX inettklog_ix_logdate
ON public.inettklog USING btree
(date)
TABLESPACE pg_default;
Your table is extremely bloated. Given your other question, this extreme bloat is not surprising.
You can fix this with a VACUUM FULL.
Going forward, you should avoid getting into this situation in the first place, by deleting records as they become obsolete rather than waiting until 99.998% of them are obsolete before acting.
I have trigger function that automatically creates child tables based on date column from parent table (table 1). Hovewer I have to make modification to do that based on date column from another table (table 2)!
Is this possible at all? I have foreign key in table 1 which is linked with a id column in table 2.
I searched over the internet but mostly found different scripts for task I already solved (date column in parent table, not in another table).
EXAMPLE: Make monthly partitions of table invoice_details based on invoice_date in table invoice (foreign key invoice_details.invoice_id - > invoice.invoice_id)
CREATE TABLE public.invoice_details
(
id integer NOT NULL,
invoice_id integer NOT NULL,
charge_type integer,
charge_amount numeric(15,5),
charge_tax numeric(15,5),
charge_status character varying COLLATE pg_catalog."default")
TABLESPACE pg_default;
CREATE TABLE public.invoice
(
invoice_id integer NOT NULL,
customer character varying COLLATE pg_catalog."default",
invoice_date date NOT NULL)
I have a table that is partitoned on time field. I have 25 partitions. Now I consider partitioning it further more using object type field. I have ten object types so it will result in 250 partitions. According to what I read, the recommended partition number is few dozens but in my cases the schema is very simple and doesn't include any joins so I wonder if it's o.k. to define that many partitions. I am using postgres version 9.1.2
CREATE TABLE metric_store.lc_aggregated_data_master_10_minutes
(
from_time integer,
object_id integer,
object_type integer,
latencies_client_fetch_sec_sum bigint,
latencies_client_rttsec_sum bigint,
latencies_db_bci_res_sec_sum bigint,
latencies_net_infrastructure_ttlb_sec_sum bigint,
latencies_retransmissions_sec_sum bigint,
latencies_ttfbsec_sum bigint,
latencies_ttlbsec_sum bigint,
latencies_ttlbsec_sumsqr bigint,
latencies_ttlbsec_histogram_level0 integer,
latencies_ttlbsec_histogram_level1 integer,
latencies_ttlbsec_histogram_level2 integer,
latencies_ttlbsec_histogram_level3 integer,
latencies_ttlbsec_histogram_level4 integer,
latencies_ttlbsec_histogram_level5 integer,
latencies_ttlbsec_histogram_level6 integer,
latencies_ttlbsec_histogram_level7 integer,
usage_bytes_total bigint,
usage_hits_total integer,
latencies_server_net_ttlbsec_sum bigint,
latencies_server_rttsec_sum bigint,
avaiability_errors_total integer
)
WITH (
OIDS=FALSE
);
ALTER TABLE metric_store.lc_aggregated_data_master_10_minutes
OWNER TO postgres;
CREATE TABLE metric_store.lc_aggregated_data_10_minutes_from_1353070800
(
CONSTRAINT lc_aggregated_data_10_minutes_from_1353070800_pkey PRIMARY KEY (from_time , object_id ),
CONSTRAINT lc_aggregated_data_10_minutes_from_1353070800_from_time_check CHECK (from_time >= 1353070800 AND from_time < 1353190800)
)
INHERITS (metric_store.lc_aggregated_data_master_10_minutes)
WITH (
OIDS=FALSE
);
ALTER TABLE metric_store.lc_aggregated_data_10_minutes_from_1353070800
OWNER TO postgres;
CREATE INDEX lc_aggregated_data_10_minutes_from_1353070800_obj_typ_idx
ON metric_store.lc_aggregated_data_10_minutes_from_1353070800
USING btree
(from_time , object_type );
The current version (9.2) has this guidance about the number of partitions. (That guidance hasn't changed since 8.3.)
All constraints on all partitions of the master table are examined
during constraint exclusion, so large numbers of partitions are likely
to increase query planning time considerably. Partitioning using these
techniques will work well with up to perhaps a hundred partitions;
don't try to use many thousands of partitions.
From reading the PostgreSQL mailing lists, I believe increasing the time for query planning is the main problem you face.
If your partitions can segregate hot data from cold data, or if your partitions can group clustered sets of data you frequently query, you will probably be ok. But testing is your best bet. EXPLAIN ANALYZE representative queries in the unpartitioned table, then do the same after partitioning. Choose representative queries before you analyze any of them.