/*
* We are using UPSERT feature from PostgreSQL 9.5
- * to have the better performance,
- * set the minimum version to 90500
+ * to have the better performance where possible.
*/
if (m_pgversion < 90500) {
- throw DatabaseException("PostgreSQL database error: "
- "Server version 9.5 or greater required.");
+ warningstream << "Your PostgreSQL server lacks UPSERT "
+ << "support. Use version 9.5 or better if possible."
+ << std::endl;
}
infostream << "PostgreSQL Database: Version " << m_pgversion
"WHERE posX = $1::int4 AND posY = $2::int4 AND "
"posZ = $3::int4");
- prepareStatement("write_block",
+ if (m_pgversion < 90500) {
+ prepareStatement("write_block_insert",
+ "INSERT INTO blocks (posX, posY, posZ, data) SELECT "
+ "$1::int4, $2::int4, $3::int4, $4::bytea "
+ "WHERE NOT EXISTS (SELECT true FROM blocks "
+ "WHERE posX = $1::int4 AND posY = $2::int4 AND "
+ "posZ = $3::int4)");
+
+ prepareStatement("write_block_update",
+ "UPDATE blocks SET data = $4::bytea "
+ "WHERE posX = $1::int4 AND posY = $2::int4 AND "
+ "posZ = $3::int4");
+ } else {
+ prepareStatement("write_block",
"INSERT INTO blocks (posX, posY, posZ, data) VALUES "
"($1::int4, $2::int4, $3::int4, $4::bytea) "
"ON CONFLICT ON CONSTRAINT blocks_pkey DO "
"UPDATE SET data = $4::bytea");
+ }
prepareStatement("delete_block", "DELETE FROM blocks WHERE "
"posX = $1::int4 AND posY = $2::int4 AND posZ = $3::int4");
};
const int argFmt[] = { 1, 1, 1, 1 };
- execPrepared("write_block", ARRLEN(args), args, argLen, argFmt);
+ if (m_pgversion < 90500) {
+ execPrepared("write_block_update", ARRLEN(args), args, argLen, argFmt);
+ execPrepared("write_block_insert", ARRLEN(args), args, argLen, argFmt);
+ } else {
+ execPrepared("write_block", ARRLEN(args), args, argLen, argFmt);
+ }
return true;
}