support older PostGreSQL versions (#4999)

* support older PostGreSQL versions
* documentation accuracy

* improve performance by affecting less rows in UPDATE queries
This commit is contained in:
zeuner 2017-01-09 17:03:13 +01:00 committed by Ner'zhul
parent 73fdb63597
commit 11df7e886a
2 changed files with 26 additions and 7 deletions

@ -178,7 +178,7 @@ ENABLE_FREETYPE - Build with FreeType2; Allows using TTF fonts
ENABLE_GETTEXT - Build with Gettext; Allows using translations
ENABLE_GLES - Search for Open GLES headers & libraries and use them
ENABLE_LEVELDB - Build with LevelDB; Enables use of LevelDB map backend
ENABLE_POSTGRESQL - Build with libpq; Enables use of PostgreSQL map backend (PostgreSQL 9.5 or greater required)
ENABLE_POSTGRESQL - Build with libpq; Enables use of PostgreSQL map backend (PostgreSQL 9.5 or greater recommended)
ENABLE_REDIS - Build with libhiredis; Enables use of Redis map backend
ENABLE_SPATIAL - Build with LibSpatial; Speeds up AreaStores
ENABLE_SOUND - Build with OpenAL, libogg & libvorbis; in-game Sounds

@ -80,12 +80,12 @@ void Database_PostgreSQL::connectToDatabase()
/*
* 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
@ -125,11 +125,25 @@ void Database_PostgreSQL::initStatements()
"WHERE posX = $1::int4 AND posY = $2::int4 AND "
"posZ = $3::int4");
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");
@ -218,7 +232,12 @@ bool Database_PostgreSQL::saveBlock(const v3s16 &pos,
};
const int argFmt[] = { 1, 1, 1, 1 };
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;
}