From 87c21bb9412c8ba2727dec5ebcd74d44c2232d11 Mon Sep 17 00:00:00 2001 From: Alexander Korotkov Date: Sun, 7 Apr 2024 00:58:09 +0300 Subject: Implement ALTER TABLE ... SPLIT PARTITION ... command This new DDL command splits a single partition into several parititions. Just like ALTER TABLE ... MERGE PARTITIONS ... command, new patitions are created using createPartitionTable() function with parent partition as the template. This commit comprises quite naive implementation which works in single process and holds the ACCESS EXCLUSIVE LOCK on the parent table during all the operations including the tuple routing. This is why this new DDL command can't be recommended for large partitioned tables under a high load. However, this implementation come in handy in certain cases even as is. Also, it could be used as a foundation for future implementations with lesser locking and possibly parallel. Discussion: https://postgr.es/m/c73a1746-0cd0-6bdd-6b23-3ae0b7c0c582%40postgrespro.ru Author: Dmitry Koval Reviewed-by: Matthias van de Meent, Laurenz Albe, Zhihong Yu, Justin Pryzby Reviewed-by: Alvaro Herrera, Robert Haas, Stephane Tachoires --- src/backend/utils/adt/ruleutils.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'src/backend/utils/adt/ruleutils.c') diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c index c9e3ac88cb1..411841047d3 100644 --- a/src/backend/utils/adt/ruleutils.c +++ b/src/backend/utils/adt/ruleutils.c @@ -13241,3 +13241,21 @@ get_range_partbound_string(List *bound_datums) return buf->data; } + +/* + * get_list_partvalue_string + * A C string representation of one list partition value + */ +char * +get_list_partvalue_string(Const *val) +{ + deparse_context context; + StringInfo buf = makeStringInfo(); + + memset(&context, 0, sizeof(deparse_context)); + context.buf = buf; + + get_const_expr(val, &context, -1); + + return buf->data; +} -- cgit v1.2.3