摘要:
A data server of a data processing system is operably coupled to a database and in communication with a middleware server. A connection between the data server and the middleware server is established and managed. A set of attributes identifying trusted middleware servers is instituted with the data server. The middleware server transmits a connection request to the data server. The connection request has request attributes including identifying the connection request as being for a new connection or reuse of an existing connection with different connection request attributes. A connection with the middleware server is established by the data server based on the connection request. A connection status message is received by the middleware server from the data server indicating a status of the connection request. A trust indicator for the connection is established at the data server according to a trust status identified by the set of attributes for the middleware server.
摘要:
A method and system for establishing a connection between a data server and a middleware server is disclosed. The method and system include defining a plurality of trust attributes corresponding to a trusted context between the middleware server and the data server and validating the plurality of trust attributes against a plurality of attributes corresponding to the middleware server. The plurality of attributes provided in a connection request. The method and system also include establishing the trusted context based on the validating the plurality of trust attributes.
摘要:
A system, computer usable medium and computer-based method for supporting named memory variables in an information retrieval system including a relational database. PUBLIC and PRIVATE named memory variables can be created, referenced, modified or deleted using SQL statements. The information retrieval system allocates a memory area as a named variable storage space for storing named memory variables. System catalogs may be used for storing information about PUBLIC, SECURE PUBLIC, PRIVATE, SECURE PRIVATE and pre-defined named memory variables. PUBLIC and PRIVATE named memory variables can be used for transferring information between SQL statements of one or more sessions or for retrieving system information from the relational database. Both PUBLIC and PRIVATE types can be defined as SECURE named memory variables requiring specific authorization privileges to read or write to the variable.
摘要:
In a method and system for avoiding section collision for application server requests over a single database connection, the database server assigns query identifiers to each instance of the same cursor opened for the same processing level within an application, allowing multiple instances of the same cursor to be processed in parallel without section collision. The application server assigns a command source identifier to each statement sent over a single database connection to uniquely identify the application source of the statement. This applies for multiples of the same statement sent by different application sources within the same application, for a single statement containing multiple application sources, and for multiple statements from different applications multiplexed over a single database connection. These statements can be processed separately from and in parallel with the each other without section collision.
摘要:
An access control system and access control methods provide multilevel and mandatory access control for a database management system. The access control techniques provide access control at the row level in a relational database table. The database table contains a security label column within which is recorded a security label that is defined within a hierarchical security scheme. A user's security label is encoded with security information concerning the user. When a user requests access to a row, a security mechanism compares the user's security information with the security information in the row. If the user's security dominates the row's security, the user is given access to the row.
摘要:
A method, apparatus and program storage device readable by a computer tangibly embodying a program of instructions executable by the computer is provided for reorganization of database data. The computer database reorganization method reorganizes one set of database data blocks at a time, allowing concurrent data manipulation. Method identifies a set of data blocks for reorganization in a sliding peephole mode, re-orders the set of data blocks and replaces the original set of data blocks with the re-ordered set of data blocks, if possible. Preferred embodiments include an overlapping peephole method, which chooses, for each set of data block to be reorganized, a next succeeding set of data blocks plus an overlap segment, wherein the overlap segment includes a set of empty pages other than intentionally specified free pages, and the overlap segment is a subset of the preceding set of data blocks.
摘要:
An improved automatically updated timestamp for database systems is disclosed. The automatically updated timestamp can be provided in a hidden timestamp column for a table, where the value of the timestamp column can be retrieved with a query that calls the column by name. Optionally, the timestamp column can be provided for each table in the database system to ensure its availability to applications. For cases where a timestamp for each row in a table is not desired, an automatically updated timestamp can be provided for a data page. This timestamp can be retrieved from an update timestamp recorded on disk and in the buffer pool or from a log relative byte address. Although this is a page-level timestamp, its use may be desirable for infrequently updated tables or where space on the disk and buffer pool is at a premium.
摘要:
An access control system provides multilevel and mandatory access control for a database management system. The access control systems provide access control at the row level in a relational database table. The database table contains a security label column within which is recorded a security label that is defined within a hierarchical security scheme. A user's security label is encoded with security information concerning the user. When a user requests access to a row, a security mechanism compares the user's security information with the security information in the row. If the user's security dominates the row's security, the user is given access to the row.
摘要:
Techniques are provided for tuning work. In response to identifying a trigger for a work, automatic tuning is invoked. The trigger indicates that a performance goal for the work has been missed. The work is analyzed. A tuning operation is selected for the work based on a tuning history. The selected tuning operation is implemented for the work.
摘要:
Techniques are provided for supporting versions of a routine. A first version of the routine is created. A second version of the routine is generated in response to receiving an alter statement including an add version clause. The second version of the routine is activated in response to receiving an alter statement including an activate version clause.