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公开(公告)号：BR8906000A
公开(公告)日：1990-06-19
申请号：BR8906000
申请日：1989-11-29
Applicant: IBM
Abstract: A database management pre-compiler for a host programming language contains a language dependent portion and a language independent portion. The language dependent portion extracts source file statements written in a supplemental language and converts them into a language independent format. The language independent statements are communicated to the language independent portion, which translates them into lists of tasks to be performed. These tasks are communicated back to the language dependent portion in a language independent format. The language dependent portion then translates the tasks into procedure calls in the host language.
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公开(公告)号：BR8901647A
公开(公告)日：1989-11-21
申请号：BR8901647
申请日：1989-04-07
Applicant: IBM
Inventor： CHANG PHILIP YEN-TANG , COYLE DANIEL JEROME JR , HOWIE LAUREN DENISE , LINDSAY BRUCE GILBERT
Abstract: A plurality of packed descriptions is provided as a column in a table each entry containing data defining attributes associated with a different object (such as a table or view defined to the database) and all its component objects (such as related columns and indexes). Accessing the row corresponding to a particular object returns a description of all of the attributes of the object's component objects, as well as information describing the object itself. The packed description information is redundantly stored conventionally in other system catalogs for use IN at IN querying physical definitions of objects in a manner consistent with other database products. The database state information comprising the packed descriptions is retained in internal format whereas the correlative redundant information is in a user-readable external format. By denormalising the schema for schema data whereby identifying relationships between objects is simplified, time required for compilation of statements referencing objects is substantially reduced. All information concerning attributes of an object specified in statement and its component objects necessary to compile the statement may thereby be fetched from the packed description field corresponding to the object in one I/O operation. Objects' descriptions must otherwise be retrieved from numerous I/Os to separate system catalogs and rows collectively containing the descriptions.
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公开(公告)号：DE3278297D1
公开(公告)日：1988-05-05
申请号：DE3278297
申请日：1982-04-21
Applicant: IBM
Inventor： CHANG PHILIP YEN-TANG , HOFFMAN VIRGINIA MARIE , MCINROY JOHN WISE
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公开(公告)号：BR8901648A
公开(公告)日：1989-11-21
申请号：BR8901648
申请日：1989-04-07
Applicant: IBM
Inventor： CHANG PHILIP YEN-TANG , ENGLES ROBERT WILLIAM , OBERMANN DAVID FRANCIS , TRUMBLE MARY KATHLEEN
IPC: G06F17/30 , G06F20060101 , G06F15/40
Abstract: A relational database system having mixed data comprises means for selectively designating a column in a database table as being for single byte character set data only. Preferably, the user application can specify the subtype of character data within a column as the column is created or added by specifying FOR SBCS or FOR MIXED in either the CREATE TABLE statement or the ALTER TABLE statement. This can be done by specifying the subtype of the character data types including CHAR, VARCHAR, and LONG VARCHAR. Along with specifying the subtype as either for single byte data or for mixed data, means are preferably provided for specifying the codepage to be used for the column of the table in the database. The subtype of the character can then be recorded in terms of the code page attributes of the character data type as stored in the database system catalogs. This encoding scheme provides an efficient method of determining whether a column is only for single byte character set data or mixed data, and at the same time knowing the correct codepage that is to be used for that column simply by querying the code page columns within the database system catalogs.
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公开(公告)号：BR8901643A
公开(公告)日：1989-11-21
申请号：BR8901643
申请日：1989-04-07
Applicant: IBM
Inventor： CHANG PHILIP YEN-TANG , CROSS MICHAEL RAY
Abstract: Strings of characters are ordered automatically in a computer system by comparing the weights of the characters of each pair of corresponding characters in a first and second of the strings of characters; comparing the numerical character codes of a first pair of the corresponding characters which are determined to have equal weights; and positioning a character string having a corresponding character with a lower numerical character code to have a predetermined order with respect to the other of the first and second character strings when all pairs of corresponding characters succeeding the first pair also have equal weights. This results in automated alphabetising of character strings which is consistent regardless of the order in which the character strings are sorted, while retaining the flavour of the language conventions when possible, and while providing a solution not requiring substantial extra computing power.
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Patent Agency Ranking
公开(公告)号：PT90209A
公开(公告)日：1989-11-10
申请号：PT9020989
申请日：1989-04-06
Applicant: IBM
Inventor： CHANG PHILIP YEN-TANG , OBERMANN DAVID F , TRUMBLE MARY K
IPC: G06F17/30 , G06F20060101 , G06F
Abstract: A relational database system having mixed data comprises means for selectively designating a column in a database table as being for single byte character set data only. Preferably, the user application can specify the subtype of character data within a column as the column is created or added by specifying FOR SBCS or FOR MIXED in either the CREATE TABLE statement or the ALTER TABLE statement. This can be done by specifying the subtype of the character data types including CHAR, VARCHAR, and LONG VARCHAR. Along with specifying the subtype as either for single byte data or for mixed data, means are preferably provided for specifying the codepage to be used for the column of the table in the database. The subtype of the character can then be recorded in terms of the code page attributes of the character data type as stored in the database system catalogs. This encoding scheme provides an efficient method of determining whether a column is only for single byte character set data or mixed data, and at the same time knowing the correct codepage that is to be used for that column simply by querying the code page columns within the database system catalogs.
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公开(公告)号：PT90209B
公开(公告)日：1995-06-30
申请号：PT9020989
申请日：1989-04-06
Applicant: IBM
Inventor： CHANG PHILIP YEN-TANG , OBERMANN DAVID F , TRUMBLE MARY K
IPC: G06F17/30 , G06F20060101 , G06F15/40
Abstract: A relational database system having mixed data comprises means for selectively designating a column in a database table as being for single byte character set data only. Preferably, the user application can specify the subtype of character data within a column as the column is created or added by specifying FOR SBCS or FOR MIXED in either the CREATE TABLE statement or the ALTER TABLE statement. This can be done by specifying the subtype of the character data types including CHAR, VARCHAR, and LONG VARCHAR. Along with specifying the subtype as either for single byte data or for mixed data, means are preferably provided for specifying the codepage to be used for the column of the table in the database. The subtype of the character can then be recorded in terms of the code page attributes of the character data type as stored in the database system catalogs. This encoding scheme provides an efficient method of determining whether a column is only for single byte character set data or mixed data, and at the same time knowing the correct codepage that is to be used for that column simply by querying the code page columns within the database system catalogs.
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公开(公告)号：BR8901616A
公开(公告)日：1989-11-21
申请号：BR8901616
申请日：1989-04-06
Applicant: IBM
Inventor： CHANG PHILIP YEN-TANG , COYLE DANIEL JEROME JR , MALKEMUS MOTHY RAY , RODRIGUEZ REBECCA ANNE , WELTI PHILIP JOHN
Abstract: In a relational database system, a method is used that increases the performance of the sort operation. An optimiser routine in the relational database manager analyses a user's complete query to determine whether the final sorted results can be used directly by the user as sorting occurs. If the sort results can be used, the sort results are sent to Relational Data Services in the relational database manager for output to the user. Depending upon the determination made by the optimiser routine, one of two output modes for the final sorted sequence string of data are selected by the relational database manager. In disk output mode, the last pass of the final sorted sequence string is written to disk. In fast direct output mode, the records of data are sent to the user as the final sorted sequence string is being merged during the last pass. Such an arrangement reduces the total sort time by eliminating the overhead of writing to disk during the fast direct output mode. Also, the response time, or availability for each record is reduced since each record is retrieved or sent to the Relational Data Services immediately after it has been sorted into the final sort order instead of completing the entire sort first, and then writing to disk.
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