Fix schema synchronization for partitioned tables with PostgreSQL 12+

[nlenepveu]

Consider partitioned tables as regular tables

Typeorm currently excludes partitioned tables from schema synchronization. We could also take them into account as their behavior regarding schema modifications is the same as regular tables.

Ignore foreign keys on partitions of the partitioned tables when syncing schema on PostgreSQL 12+

When a table has foreign keys referencing a partitioned table, the PostgresQueryRunner will load the constraints from every partition.
We need to ignore those foreign keys as they are not managed by the user.

Example:
table_A has a foreign key constraint referencing table_B which is a partitioned table on key1 and key2.

The command typeorm schema:log will return this kind of list of queries to remove the FK constraints from table_A.

------------------------------------------------------------------
-- Schema syncronization will execute following sql queries (220):
------------------------------------------------------------------
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2__fkey";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey1";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey2";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey3";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey4";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey5";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey6";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey7";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey8";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey9";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey10";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey11";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey12";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey13";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey14";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey15";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey16";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey17";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey18";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey19";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey20";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey21";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey22";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey23";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey24";
ALTER TABLE "table_A" DROP CONSTRAINT "table_A_table_B_key1_key2_fkey25";
...

Typeorm should ignore those constraints.

[pleerock]

what if we wouldn't have hasIsPartition check here? according to this check it looks like we do need items with "AND "cl"."relispartition" = 't' ?

[nlenepveu]

@pleerock the column relispartition does not exist in PostgreSQL versions that have no support for partitioned tables (prior to version 10). This is why we need this check here.
Then, when using a version of PostgreSQL with partitioned tables, we need to ignore the partitions and only check the constraints on the "main" table ie: "relispartition" = "f" (which are not partitions).

[nlenepveu]

Maybe we should rename hasPartitionedTables to hasSupportForPartitionedTables to make it clearer?

[nlenepveu]

@pleerock let me know if anything is unclear

[pleerock]

Looks good, thanks

[prevostc]

Hi there sorry to interrupt, this seem to be the only issue related to pg partitioning.
I couldn't find in the documentation how to add PARTITION BY RANGE (x,y) to the table definition.