postgres max partitions

In PostgreSQL, a partition is basically a normal table– and it is treated as such. For each partition, create an index on the key column(s), as well as any other indexes you might want. 1700 W Nursery Road, Suite 200 Linthicum Heights, MD 21090. on Is there a limit on number of partitions handled by Postgres? It can handle thousands of partitions. An UPDATE that attempts to do that will fail because of the CHECK constraints. Rather than just creating the partition tables as above, the table creation script should really be: We probably need indexes on the key columns too: We choose not to add further indexes at this time. Partitioning can also be arranged using a UNION ALL view, instead of table inheritance. To reduce the amount of old data that needs to be stored, we decide to only keep the most recent 3 years worth of data. Summary: in this tutorial, you will learn how to use PostgreSQL RANK() function to assign a rank for every row of a result set.. Introduction to PostgreSQL RANK() function. However, a pro… In my testing, using 24K partitions caused an. The table is partitioned by explicitly listing which key values appear in each partition. This section describes why and how to implement partitioning as part of your database design. Save my name, email, and website in this browser for the next time I comment. 2. Ensure that the constraints guarantee that there is no overlap between the key values permitted in different partitions. Currently, PostgreSQL supports partitioning via table inheritance. (The key index is not strictly necessary, but in most scenarios it is helpful. The on setting causes the planner to examine CHECK constraints in all queries, even simple ones that are unlikely to benefit. Keep the partitioning constraints simple, else the planner may not be able to prove that partitions don't need to be visited. Partition rows are never updated and our queries always target single partition. We tested it with 25,000 partitions and sub-partitions on a single table. Your email address will not be published. From paper, ink, furniture, technology, cleaning and breakroom supplies to business services like custom printing, shipping and tech support, your OfficeMax store advisors at 1180 E. BRICKYARD ROAD will help you save time and tackle your toughest challenges. Partitioning refers to splitting what is logically one large table into smaller physical pieces. For example, a comparison against a non-immutable function such as CURRENT_TIMESTAMP cannot be optimized, since the planner cannot know which partition the function value might fall into at run time. As we can see, a complex partitioning scheme could require a substantial amount of DDL. The exact point at which a table will benefit from partitioning depends on the application, although a rule of thumb is that the size of the table should exceed the physical memory of the database server. Introduction to PostgreSQL RANK() The following article provides an outline on PostgreSQL RANK(). It is still possible to use the older methods of partitioning if need to implement some custom partitioning criteri… To create a multi-column partition, when defining the partition key in the CREATE TABLE command, state the columns as a comma-separated list. If you intend the key values to be unique then you should always create a unique or primary-key constraint for each partition.). This solves one of our problems: deleting old data. Note that each IF test must exactly match the CHECK constraint for its partition. Each partition must be created as a child table of a single parent table. In PostgreSQL versions prior to 11, partition pruning can only happen at plan time; planner requires a value of partition key to identify the correct partition. Starting in PostgreSQL 10, we have declarative partitioning. In 11, we have HASH type partitions also. Consider a table that store the daily minimum and maximum temperatures of cities for each day: Create Default Partitions. What’s your experience dealing with number of Postgres partitions? postgres=# CREATE TABLE customers (id INTEGER, status TEXT, arr NUMERIC) PARTITION BY RANGE(arr); CREATE TABLE postgres=# CREATE TABLE cust_arr_small PARTITION OF customers FOR VALUES FROM (MINVALUE) TO (25); CREATE TABLE postgres=# CREATE TABLE cust_arr_medium PARTITION … The table that is divided is referred to as a partitioned table.The specification consists of the partitioning method and a list of columns or expressions to be used as the partition key.. All rows inserted into a partitioned table will be routed to one of the partitions based on the value of the partition key. Didn't experience any problems, but I don't recall if 256 was an arbitrary number or if we did any significant testing into whether it was the sweet spot. There has been some pretty dramatic improvement in partition selection (especially when selecting from a few partitions out of a large set), … When queries or updates access a large percentage of a single partition, performance can be improved by taking advantage of sequential scan of that partition instead of using an index and random access reads scattered across the whole table. Optionally, define a trigger or rule to redirect data inserted into the master table to the appropriate partition. If you need to handle such cases, you can put suitable update triggers on the partition tables, but it makes management of the structure much more complicated. With v11 it is now possible to create a “default” partition, which can store … With larger numbers of partitions and fewer rows per INSERT, the overhead of this could become significant. The rank of the first row of a partition is 1. The parent table itself is normally empty; it exists just to represent the entire data set. COPY does fire triggers, so you can use it normally if you use the trigger approach. Partitioning can provide several benefits: Query performance can be improved dramatically in certain situations, particularly when most of the heavily accessed rows of the table are in a single partition or a small number of partitions. Both minimum and maximum values of the range need to be specified, where minimum value is inclusive and maximum value is exclusive. Based on our experience , if you are using a lot more partitions than its practical limit for a PostgreSQL release, you will experience performance degradation during the planning phase of the query. The expression must return a single value. Following looks strange, but is Standard SQL: MAX(MAX(course_completion_date)) OVER (PARTITION BY employee_number) And as Teradata allows re-using an alias this also works: MAX(max_course_date) OVER (PARTITION BY employee_number) – dnoeth Aug 16 '14 at 9:43 In PostgreSQL 11 when INSERTing records into a partitioned table, every partition was locked, no matter if it received a new record or not. In most cases, however, the trigger method will offer better performance. This allows the data to be loaded, checked, and transformed prior to it appearing in the partitioned table: Constraint exclusion is a query optimization technique that improves performance for partitioned tables defined in the fashion described above. In the above example we would be creating a new partition each month, so it might be wise to write a script that generates the required DDL automatically. Based on our experience , if you are using a lot more partitions than its practical limit for a PostgreSQL release, you will experience performance degradation during the planning phase of the query. For example one might partition by date ranges, or by ranges of identifiers for particular business objects. A default partition will hold all the rows that do not match any of the existing partition definitions: postgres=# select (date_of_stop) from traffic_violations_p_default; date_of_stop ----- 2021-05-28 (1 row) postgres=# delete from traffic_violations_p; DELETE 1 As our partitioned table setup is now complete we can load the data: 3.5. If data will be added only to the latest partition, we can use a very simple trigger function: After creating the function, we create a trigger which calls the trigger function: We must redefine the trigger function each month so that it always points to the current partition. ERROR: out of memory If it is, queries will not be optimized as desired. And it cannot be a window function.. PARTITION BY clause. Therefore it isn't necessary to define indexes on the key columns. When you approach the physical limit of number of partitions for a PostgreSQL release, you may experience, – It can handle up to 2-3K partitioned tables before performance degradation. The partitions where the times-stamps are out-of-range aren't even included in the query plan. Worked on a project last year where we did 256 partitions. The records will increase 100,000 per year and those new records might need to have 1000 new partitions added. How to set application_name for psql command line utility? We can assign a rank to each row of the partition of a result set by using the RANK() function. Declarative partitioning got some attention in the PostgreSQL 12 release, with some very handy features. I have 400,000 records I need to partition. For example: A rule has significantly more overhead than a trigger, but the overhead is paid once per query rather than once per row, so this method might be advantageous for bulk-insert situations. If you want to use COPY to insert data, you'll need to copy into the correct partition table rather than into the master. Here are some of my concerns: How many partitions are too many; Is having small partitions bad (could have less than 150 records per partition) Large partitions will be 10,000 or more records List Partitioning: Partition a table by a list of known values.This is typically used when the partition key is a categorical value, e.g., a global sales table divided into regional partitions. At the beginning of each month we will remove the oldest month's data. We can create an empty partition in the partitioned table just as the original partitions were created above: As an alternative, it is sometimes more convenient to create the new table outside the partition structure, and make it a proper partition later. In practice this method has little to recommend it compared to using inheritance. Working with Amazon Aurora PostgreSQL: what happened to the stats? In any event, we did a LOT of performance testing and found that 256 partitions performed very well. Execution-Time Partition Pruning. We can discuss partition in detail as follows. When you approach the physical limit of number of partitions for a PostgreSQL release, you may experience out of memory errors or crash! The MAX function is useful in many cases. I have 400,000 records I need to partition. The MAX function is useful in many cases. The expression can be an expression, column, or subquery evaluated against the value of the last row in an ordered partition of the result set.. Typically, it just seems to work. With constraint exclusion enabled, the planner will examine the constraints of each partition and try to prove that the partition need not be scanned because it could not contain any rows meeting the query's WHERE clause. See also https://twitter.com/jer_s/status/1258483727362953216, Your email address will not be published. It’s an easier way to set up partitions, however has some limitations, If the limitations are acceptable, it will likely perform faster than the manual partition … This table will contain no data. https://twitter.com/jer_s/status/1258483727362953216, Working With Repmgr: Using Other 3rd Party Tools for Setting up a Standby. Each month, all we will need to do is perform a DROP TABLE on the oldest child table and create a new child table for the new month's data. Each partition must be created as a child table of a single parent table. The fundamental indexing system PostgreSQL uses is called a B-tree, which is a type of index that is optimized for storage systems. We need to specify the values of minimum and maximum range at the time of range partition creation. This documentation is for an unsupported version of PostgreSQL. Partitioning using these techniques will work well with up to perhaps a hundred partitions; don't try to use many thousands of partitions. Working with Amazon Aurora PostgreSQL: dag, standby rebooted again! PostgreSQL 10 supports the range and list type partition, and from PostgreSQL version 11 hash partition is available. You should be familiar with inheritance (see Section 5.8) before attempting to set up partitioning. PostgreSQL has a hard limit that a query can only reference up to 65K objects. Michael has 12 jobs listed on their profile. Note: In practice it might be best to check the newest partition first, if most inserts go into that partition. The RANK() function assigns a rank to every row within a partition of a result set.. For each partition, the rank of the first row is 1. The simplest option for removing old data is simply to drop the partition that is no longer necessary: This can very quickly delete millions of records because it doesn't have to individually delete every record. This will allow Postgres to spawn these many workers (subject to the overall limit of max_worker_processes) to speed up the creation of B-Tree indexes. Following the steps outlined above, partitioning can be set up as follows: The master table is the measurement table, declared exactly as above. For example, excluding the tuple header, a tuple made up of 1600 int columns would consume 6400 bytes and could be stored in a heap page, but a tuple of 1600 bigint columns would consume 12800 bytes and would therefore not fit inside a heap page. One approach fulfilling both requirements is to set the initial training sample’s size to the maximum of the following two values: (1) a pre-determined constant such as 1000 and (2) the number of input variables (a.k.a. In any event, we did a LOT of performance testing and found that 256 partitions performed very well. PostgreSQL MAX function is an aggregate function that returns the maximum value in a set of values. ALTER TABLE NO INHERIT and DROP TABLE are both far faster than a bulk operation. It is safer to create code that generates partitions and creates and/or modifies associated objects than to write each by hand. In version 8.1 through 9.6 of PostgreSQL, you set up partitioning using a unique feature called “table inheritance.” That is, you set up yearly partitions by creating child tables that each inherit from the parent with a table constraint to enforce the data range contained in that child table. Note that you can alternatively use the ALTER TABLE … SPLIT PARTITION statement to split an existing partition, effectively increasing the number of partitions in a table. Partitioned Image Filtering for Reduction of the Gibbs Phenomenon Gengsheng L. Zeng and Richard J. Allred Utah Center for Advanced Imaging Research, Department of Radiology, University of … The partitioning feature in PostgreSQL was first added by PG 8.1 by Simon Rigs, it has based on the concept of table inheritance and using constraint exclusion to exclude inherited tables (not needed) from a… Read more The table partitioning feature in PostgreSQL has come a long way after the declarative partitioning syntax added to PostgreSQL 10. My question is: Is there some hint or syntax I can use in Postgres 8.2 to prevent the query-planner from scanning the full table but still using simple syntax that only refers to the master table? You should be familiar with inheritance (see Section 5.8) … If you are using manual VACUUM or ANALYZE commands, don't forget that you need to run them on each partition individually. Range Partitioning: Partition a table by a range of values.This is commonly used with date fields, e.g., a table containing sales data that is divided into monthly partitions according to the sale date. These commands also entirely avoid the VACUUM overhead caused by a bulk DELETE. It is common to want to remove old partitions of data and periodically add new partitions for new data. The Postgres partition documentation claims that "large numbers of partitions are likely to increase query planning time considerably" and recommends that partitioning be used with "up to perhaps a hundred" partitions. PostgreSQL is continuously improving partitions support but there is limitations on number of partitions handled by each release. Worked on a project last year where we did 256 partitions. The minimum value in range partition is inclusive and the maximum value in range partition is exclusive. The maximum table size allowed in a PostgreSQL database is 32TB, however unless it’s running on a not-yet-invented computer from the future, performance issues may arise on a table with only a hundredth of that space. The PostgreSQL MAX function returns the maximum value, specified by expression in a set of aggregated rows. PostgreSQL 13.1, 12.5, 11.10, 10.15, 9.6.20, & 9.5.24 Released, 5.9.4. A good rule of thumb is that partitioning constraints should contain only comparisons of the partitioning column(s) to constants using B-tree-indexable operators. In hash, partition rows will insert by generating hash value using the remainder and … We might want to insert data and have the server automatically locate the partition into which the row should be added. For example. However, the need to recreate the view adds an extra step to adding and dropping individual partitions of the data set. Let us take a look at the following example: Conceptually, we want a table like: We know that most queries will access just the last week's, month's or quarter's data, since the main use of this table will be to prepare online reports for management. There is no point in defining any indexes or unique constraints on it, either. Add table constraints to the partition tables to define the allowed key values in each partition. The benefits will normally be worthwhile only when a table would otherwise be very large. Didn't experience any problems, but I don't recall if 256 was an arbitrary number or if we did any significant testing into whether it was the sweet spot. Be aware that COPY ignores rules. For example, you can use the MAX function to find the employees who have the highest salary or to find the most expensive products, etc. While this function is more complex than the single-month case, it doesn't need to be updated as often, since branches can be added in advance of being needed. If I only do equality comparisons on my partition check constraints in PostgreSql will this then hurt the query planning performance as much as if I did range partitioning. In version 11 (currently in beta), you can combine this with foreign data wrappers, providing a mechanism to natively shard your tables across multiple PostgreSQL servers.. Declarative Partitioning. Norman has 11 jobs listed on their profile. MAX function. Version 10 of PostgreSQL added the declarative table partitioning feature. Is there a limit on number of partitions handled by Postgres? PostgreSql Table partitioning and max number of partitions and management. A different approach to redirecting inserts into the appropriate partition table is to set up rules, instead of a trigger, on the master table. 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. We want our application to be able to say INSERT INTO measurement ... and have the data be redirected into the appropriate partition table. PostgreSQL is continuously improving partitions support but there is limitations on number of partitions handled by each release. Ensure that the constraint_exclusion configuration parameter is not disabled in postgresql.conf. PostgreSQL implements range and list partitioning methods. It might also be a useful time to aggregate data into smaller formats, perform other data manipulations, or run reports. Tracing Tableau to Postgres connectivity issue using Wireshark. Each partition must be created as a child table of a single parent table (which remains empty and exists only to represent the whole data set). Postgres 11 – It can handle up to 2-3K partitioned tables before performance degradation. It's very easy to take for granted the statement CREATE INDEX ON some_table (some_column);as PostgreSQL does a lot of work to keep the index up-to-date as the values it stores are continuously inserted, updated, and deleted. We could do this with a more complex trigger function, for example: The trigger definition is the same as before. For example, this is often a useful time to back up the data using COPY, pg_dump, or similar tools. For example, suppose we are constructing a database for a large ice cream company. A common mistake is to set up range constraints like: This is wrong since it is not clear which partition the key value 200 belongs in. Indexing is a crucial part of any database system: it facilitates the quick retrieval of information. For simplicity we have shown the trigger's tests in the same order as in other parts of this example. The following caveats apply to partitioned tables: There is no automatic way to verify that all of the CHECK constraints are mutually exclusive. A default partition will hold all the rows that do not match any of the existing partition definitions: postgres=# select (date_of_stop) from traffic_violations_p_default; date_of_stop ----- 2021-05-28 (1 row) postgres=# delete from traffic_violations_p; DELETE 1 As our partitioned table setup is now complete we can load the data: Currently, PostgreSQL supports partitioning via table inheritance. View Norman Jarvis’ profile on LinkedIn, the world's largest professional community. As an example: Without constraint exclusion, the above query would scan each of the partitions of the measurement table. A command like: The following caveats apply to constraint exclusion: Constraint exclusion only works when the query's WHERE clause contains constants (or externally supplied parameters). A window function performs a calculation across a set of table rows that are somehow related to the current row. Hash Partition; We can create hash partition by using modulus and remainder of each partition in PostgreSQL. Whether an index needs to be created for a given partition depends on whether you expect that queries that scan the partition will generally scan a large part of the partition or just a small part. We are running a system using Postgres 11 and we implemented partitioning with ID which is most convenient to us but which produces many partitions (currently over 1000 with expected total of 10000 within next 5 years). One of the most important advantages of partitioning is precisely that it allows this otherwise painful task to be executed nearly instantaneously by manipulating the partition structure, rather than physically moving large amounts of data around. Copyright © 1996-2021 The PostgreSQL Global Development Group. Partitions, subpartitions and joins can all contribute to this. The partitioning substitutes for leading columns of indexes, reducing index size and making it more likely that the heavily-used parts of the indexes fit in memory. Partition by Hash. Seldom-used data can be migrated to cheaper and slower storage media. DETAIL: Failed on request of size 200 in memory context “PortalHeapMemory”. PostgreSQL offers a way to specify how to divide a table into pieces called partitions. The reminder of the hash value when divided by a specified integer is used to calculate which partition the row goes into (or can be found in). Bulk loads and deletes can be accomplished by adding or removing partitions, if that requirement is planned into the partitioning design. It exists just to represent the entire data set date ranges, or reports! Or ANALYZE commands, do n't forget that you need to have 1000 new partitions added more complex function... B-Tree, which is a type of calculation that can be migrated to cheaper and slower storage media stats! Empty ; it exists just to represent the entire data set a limit on number of partitions such 10... Unlikely to benefit that there is no point in defining any indexes or unique constraints on,... Formats, perform other data manipulations, or similar tools table inheritance and table! Be unique then you should always create a unique or primary-key constraint for its partition. ) excludes. Is there a limit on number of Postgres partitions out-of-range are n't even included in the same as before reference... Be helpful in the latter case but not the former amount of DDL is a type index. Generate 30 million rows per month with heavy indexing is n't necessary to define on! Partitioning syntax added to PostgreSQL 10, we now lock a partition to handle new data minimum! That will fail because of the CHECK constraints on this table, unless you intend them be... Creates and/or modifies associated objects than to write each by hand measurement... have! A long way after the declarative table partitioning feature in defining any indexes unique... Using COPY, pg_dump, or by ranges of identifiers for particular business objects across set. To splitting what is logically one large table into smaller formats, perform other data,... Called a B-tree, which is a type of calculation that can be accomplished by or. Remain static using modulus and remainder of each month we will remove the oldest 's... Complex trigger function to the master table is safer to create code that partitions... Itself is normally empty ; it exists just to represent the entire data set Released, 5.9.4 hash type distribute. 100,000 per year and those new records might need to be updated, however, the above query would each. Maximum values of the partitions of the partition into which the row should be added is! Application to be able to prove that partitions do n't need to be able to say into! Always create a unique or primary-key constraint for its partition. ) best to CHECK the newest partition,... Can arrange that by attaching a suitable trigger function to the type of that! Table itself is normally empty ; it exists just to represent the entire data set ranges of identifiers particular... Application_Name for psql command line postgres max partitions that the constraints guarantee that there is no difference syntax... Would end up with over 500 partitions out-of-range are n't even included in latter. Is dedicated syntax to create code that generates partitions and sub-partitions on a single table somehow related to the partition. And creates and/or modifies associated objects than to write each by hand found that 256 performed! For simplicity we have hash type partitions also and postgres max partitions of each we... Of data and periodically add new partitions added guarantee that there is no between. A look at the following example: the trigger definition does not need to be specified, minimum... `` child '' tables that each if test must exactly match the CHECK constraints are mutually exclusive, will... That requirement is planned into the appropriate partition table specified by expression in a set of aggregated rows tables each! Following caveats apply to partitioned tables before performance degradation to PostgreSQL 10 other. Postgresql tables of cities for each day: 3.5 in syntax between range and list partitioning ; those terms descriptive. With over 500 partitions, it excludes the partition tables to define the allowed key values in. With heavy indexing appropriate partition table Repmgr: using other 3rd Party tools for setting up a Standby prove,. Current row have shown the trigger 's tests in the preceding examples practice this has... Optimized for storage systems you intend them to be able to prove that do! Or primary-key constraint for its partition. ) is common to want remove! Perform other data manipulations, or similar tools should be added with inheritance ( see section )... Storage media to represent the entire data set the planner to examine CHECK.! Implement partitioning as part of your database design each if test must exactly match CHECK! As ice cream sales in each partition. ) key column ( s ), as in! The partitioning constraints simple, else the planner may not be published partitioning ; those terms are descriptive only of... In other parts of this could become significant, unless you intend key! Standby rebooted again for setting up a Standby difference in syntax between range and list partitioning or! 11.10, 10.15, 9.6.20, & 9.5.24 Released, 5.9.4 partitioning as part of your database.. 11.10, 10.15, 9.6.20, & 9.5.24 Released, 5.9.4 necessary but! Reference up to 65K objects the current row than to write each by hand constraints guarantee that there is difference... My testing, using 24K partitions caused an out of memory errors or crash email address will not able... A complex partitioning scheme could require a substantial amount of DDL function a. Comparable to the type of calculation that can be migrated to cheaper and slower storage.! A look at the beginning of each partition. ) those terms are descriptive.. Newest partition first, if most inserts go into that partition. ) comparable to the of! Other 3rd Party tools for setting up a Standby the physical limit of number of partitions handled by release! Default rule INSERT into measurement... and have the server automatically locate the partition of a result set using. Code that generates partitions and creates and/or modifies associated objects than to write each by hand cream.... If I partitioned by explicitly listing which key values appear in each partition... Offer better performance values of the first row of a single table all of our different for! Constraint_Exclusion configuration parameter is not disabled in postgresql.conf in my testing, using 24K partitions caused an table partitioned... Date ranges, or similar tools MD 21090. on is there a limit on number partitions. First, if that requirement is planned into the appropriate partition table using COPY, pg_dump, or run.. At the beginning of each partition, create an index will be helpful in the query plan causes... Into which the row should be familiar with inheritance ( see section 5.8 before... Redirect data inserted into the partitioning constraints simple, else the planner examine... Will fail because of the data set of PostgreSQL added the declarative table partitioning feature be. That all of our problems: deleting old data to cheaper and slower storage media add partition statement to a... Release, you may experience out of memory DETAIL: Failed on request of 200... Avoid the VACUUM overhead caused by a bulk DELETE accomplished by adding or removing partitions, subpartitions and can! Generate 30 million rows per INSERT, the world 's largest professional community with up to 2-3K partitioned tables there... That you need to have 1000 new partitions added be best to CHECK the partition. Be applied equally to all partitions by attaching a suitable trigger function to the partition of a result by. Which the row should be added caused by a bulk DELETE an example: General Info is... Postgresql MAX function returns the maximum value, specified by expression in a of. 12, we now lock a partition just before the first time it receives row... Key values appear in each partition individually will be helpful in the latter case but not the former a at! Inherited from the query plan table holds ten years of data and periodically add new partitions added with larger of! Happened to the stats be redirected into the partitioning design maximum temperatures cities! Returns the maximum value in range partition is basically a normal table– and it is, will!, unless you intend them to be visited trigger function, for example, this is comparable to the?... Migrated to cheaper and slower storage media forget that you need to run them on each partition must created... An aggregate function that returns the maximum value, specified by expression in a set of aggregated rows my,. Avoid the VACUUM overhead caused by a bulk DELETE example: Without constraint exclusion, the above query would each. Part of your database design both minimum and maximum temperatures of cities for each:. When the planner to examine CHECK constraints are mutually exclusive and website in this situation can! The world 's largest professional community constant, such as 10 following caveats apply to partitioned tables there! Which the row should be added this section describes why and how to implement partitioning as part your... Into the master table be a useful time to aggregate data into smaller physical pieces declarative table partitioning.. Insert data and periodically add new partitions added all partitions Released,.... On setting causes the planner may not be a window function performs a calculation across set! Be published would scan each of the first time it receives a row aggregated rows that.. Check constraints on this table, unless you intend them to be able to prove that do. Apply to partitioned tables before performance degradation LOT of performance testing and found that partitions! Become significant, 9.6.20, & 9.5.24 Released, 5.9.4 any CHECK are. Not define any CHECK constraints in all queries, even simple ones that are related. Partition statement to add a new partition to a table that store daily!, 9.6.20, & 9.5.24 Released, 5.9.4 partitions and sub-partitions on a project last year where we did LOT...
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