… we can see a huge tables with varchar/char fields, with small sets of possible values. …As you can see, ENUM and VARCHAR show close performance, while join performance degraded dramatically. Here is why: … full table scan performs about 25 times better than accessing rows via index (for the case…
Post: MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark
March 11, 2013 By 7 Comments
…5.6 vs MySQL … negative performance … | +——————-+——————+——-+——+——+———+—————–+ | `ssb`.`lineorder` | GEN_CLUST_INDEX | 6001 | 2095 | 3906 | 964974 |…char(25), S_Address varchar(25), S_City char(10), S_Nation char(15), S_Region char(12), S_Phone char…
Post: Analyzing air traffic performance with InfoBright and MonetDB
October 2, 2009 By 50 Comments
…varchar(10) DEFAULT NULL, `Origin` char(5) DEFAULT NULL, `OriginCityName` varchar(100) DEFAULT NULL, `OriginState` char(2) DEFAULT NULL, `OriginStateFips` varchar(10) DEFAULT NULL, `OriginStateName` varchar…really about InfoBright vs MonetDB comparison… not have indexes like InfoBright, but…performance…
Post: MySQL 6.0 vs 5.1 in TPC-H queries
March 25, 2008 By 17 Comments
…` char(1) NOT NULL, `l_commitdate` date NOT NULL, `l_receiptdate` date NOT NULL, `l_shipinstruct` char(25) NOT NULL, `l_comment` varchar(44) NOT NULL, `l_shipmode` char(10) NOT NULL, PRIMARY KEY… index scan here. If we try to execute query with IGNORE KEY (li_shp_dt_idx) (full table scan will be performed…
Post: Common MySQL traps webinar questions followup
January 17, 2013 By 1 Comment
… so they may benefit from different indexing Q: Is there a Percona … recommendation on when to use ENUM vs. CHAR? Especially for one character values? … string, a VARCHAR(15) could be good to store such values (A CHAR(8) … course I’m biased but High Performance MySQL 3rd edition is a very …
