tailieunhanh - Rampant TechPress Oracle Data Warehouse Management PHẦN 6

Mục đích của thủ tục gather_schema_stats là để thu thập tất cả các số liệu thống kê sơ đồ cho các lược đồ quy định. Nó cố gắng để parallelize càng nhiều các công việc càng tốt, nhưng có một số hạn chế như mô tả trong các thông số cá nhân. Điều này hoạt động sẽ không parallelize nếu người dùng không có đặc quyền chọn trên các đối tượng được phân tích. | ROBO Books Monograph Data Warehousing and Oracle8i ORA-20001 Bad input value GATHER_SCHEMA_STATS The purpose of the gather_schema_stats procedure is to gather all schema statistics for the specified schema. It attempts to parallelize as much of the work as possible but there are some restrictions as described in the individual parameters. This operation will not parallelize if the user does not have select privilege on the objects being analyzed. Input arguments ownname - schema to analyze NULL means current schema estimate_percent - Percentage of rows to estimate NULL means compute. The valid range is 100 . block_sample - whether or not to use random block sampling instead of random row sampling. Random block sampling is more efficient but if the data is not randomly distributed on disk then the sample values may be somewhat correlated. Only pertinent when doing an estimate statistics. method_opt - method options of the following format the phrase SIZE 1 is required to ensure gathering statistics in parallel and for use with the phrase hidden FOR ALL INDEXED HIDDEN COLUMNS SIZE integer This value will be passed to all of the individual tables. degree - degree of parallelism NULL means use table default value granularity - the granularity of statistics to collect only pertinent if the table is partitioned DEFAULT - gather global- and partition-level statistics SUBPARTITION - gather subpartition-level statistics PARTITION - gather partition-level statistics GLOBAL - gather global statistics ALL - gather all subpartition partition and global statistics cascade - gather statistics on the indexes as well. Index statistics gathering will not be parallelized. Using this option is equivalent to running the gather_index_stats procedure on each of the indexes in the schema in addition to gathering table and column statistics. Page 58 COPYRIGHT 2003 Rampant TechPress. All Rights Reserved. ROBO Books Monograph Data Warehousing and Oracle8i stattab - The user .