c4999232ce
With the advent of qc_get_field_info, columns can now be matched.
However, there is still some undeterminism caused by the table
information not containing contextual information (exactly where
is the table used).
Further, suppose table X contains the column A and table Y contains
the column B, then given a statement like
SELECT a, b from X, Z;
we cannot know whether a is in X or Z, or b in X or Z, without being
aware of the schema, which we currently are not.
Consequently, as long as MaxScale is not aware of the schema, some
heuristics must be applied. For instance, if exactly one table is
referred to, then we can assume that columns that are not explicitly
qualified are from that table.
The rule tests are currently rather rudimentary and need to be
expanded.
# MaxScale by MariaDB Corporation The MariaDB Corporation MaxScale is an intelligent proxy that allows forwarding of database statements to one or more database servers using complex rules, a semantic understanding of the database statements and the roles of the various servers within the backend cluster of databases. MaxScale is designed to provide load balancing and high availability functionality transparently to the applications. In addition it provides a highly scalable and flexible architecture, with plugin components to support different protocols and routing decisions. MaxScale is implemented in C and makes extensive use of the asynchronous I/O capabilities of the Linux operating system. The epoll system is used to provide the event driven framework for the input and output via sockets. The protocols are implemented as external shared object modules which can be loaded at runtime. These modules support a fixed interface, communicating the entries points via a structure consisting of a set of function pointers. This structure is called the "module object". The code that routes the queries to the database servers is also loaded as external shared objects and are referred to as routing modules. An Google Group exists for MaxScale that can be used to discuss ideas, issues and communicate with the MaxScale community. Email: maxscale@googlegroups.com Forum: http://groups.google.com/forum/#!forum/maxscale Bugs can be reported in the MariaDB Corporation bugs database: https://jira.mariadb.org/projects/MXS/issues # Documentation For information about installing and using MaxScale, please refer to the documentation. It is in Markdown format. You can point your browser to the MaxScale project at GitHub. Look inside the "Documentation" directory, where you will find a file named Documentation-Contents.md. Click on that, and GitHub will show the documentation in its intended display format. The contents page lists the available documents and has links to them. If you do not want to rely on the internet, then clone the project from GitHub and point your browser to the Documentation-Contents.md file in your local file system and proceed as above.