In Sybase IQ no two users can modify data in the same table at the same time. When you try to do this you will get an error in your application, as well as in the IQ message file. In IQ you can also run into problems when your transaction tries to modify something but [...]
For Sybase IQ it is sometimes handy to reverse engineer the statements that were used to create the various IQ dbspaces. You can do this with Power Designer but not everybody has access to the tool. Below you will find a script that does a basic attempt to reverse engineer the statements for the “create [...]
Prerequisites: Assuming you know how to decipher IQ Query Plans and understanding how Indexes use the query Engine, Parallelism and output from the Index Advisor. What You Can Do to Influence DQP Scalability and Effectiveness. There are various server and database operations that affect parallelism and performance of a query. After you have maximized [...]
IQ_SYSTEM_MAIN, IQ_SHARED_TEMP, and IQ user main dbspaces are shared by all multiplex servers, and all servers need access to the same physical file. Data managed by SQL Anywhere is not shared. Each node requires a separate copy of such data. Each server has its own set of files in IQ_SYSTEM_TEMP and IQ_SYSTEM_MSG. Note: It is always recommended to [...]
Parallel = the holy grail of speed! Sometimes, but in this case it does. Why on Earth does IQ only allow you to create indexes with parallel option? Ask Sybase! BEGIN PARALLEL CREATE HG index idx_1_HG ON <table> (column_1); CREATE LF index idx_2_LF ON <table> (column_2); CREATE HG index idx_3_HG ON <table> (column_3); …… on [...]
