Thread: INSERT ON CONFLICT of "wide" table: target lists can have at most 1664 entries
INSERT ON CONFLICT of "wide" table: target lists can have at most 1664 entries
From
Justin Pryzby
Date:
Our application INSERTs data from external sources, and infrequently UPDATEs the previously-inserted data (currently, it first SELECTs to determine whether to UPDATE). I'm implementing unique indices to allow "upsert" (and pg_repack and..), but running into a problem when the table has >830 columns (we have some tables which are at the 1600 column limit, and have previously worked around that limit using arrays or multiple tables). I tried to work around the upsert problem by using pygresql inline=True (instead of default PREPAREd statements) but both have the same issue. I created a test script which demonstrates the problem (attached). It seems to me that there's currently no way to "upsert" such a wide table? I see: ./src/include/access/htup_details.h:#define MaxTupleAttributeNumber 1664 /* 8 * 208 */ ./src/backend/parser/parse_node.c- /* ./src/backend/parser/parse_node.c- * Check that we did not produce too many resnos; at the very least we ./src/backend/parser/parse_node.c- * cannot allow more than 2^16, since that would exceed the range of a ./src/backend/parser/parse_node.c: * AttrNumber. It seems safest to use MaxTupleAttributeNumber. ./src/backend/parser/parse_node.c- */ ./src/backend/parser/parse_node.c: if (pstate->p_next_resno - 1 > MaxTupleAttributeNumber) ./src/backend/parser/parse_node.c- ereport(ERROR, ./src/backend/parser/parse_node.c- (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), ./src/backend/parser/parse_node.c: errmsg("target lists can have at most %d entries", ./src/backend/parser/parse_node.c: MaxTupleAttributeNumber))); Thanks in advance for any suggestions. Justin