2018.06.20
Dbms stats.convert raw value
目次
- 1. 概要
- 2. 詳細
概要
統計情報にRAWタイプで保存された値をNUMBERやVARCHAR2に変換する役割を担います。
詳細
使用例
drop table t1 purge; create table t1(c1 varchar2(100)); insert into t1 select object_name from all_objects where rownum <= 1000 ; exec dbms_stats.gather_table_stats(user, 't1'); -- column begin print_table(' select s.table_name, s.column_name, s.num_distinct, s.num_nulls, s.density, s.low_value, s.high_value, s.histogram from user_tab_cols s where s.table_name = upper(t1) '); end; / TABLE_NAME : T1 COLUMN_NAME : C1 NUM_DISTINCT : 992 NUM_NULLS : 0 DENSITY : .00100806451612903 LOW_VALUE : 41434345535324 HIGH_VALUE : 5741524E494E475F53455454494E475324 HISTOGRAM : NONE var min_value varchar2(100); var max_value varchar2(100); begin dbms_stats.convert_raw_value('41434345535324', :min_value); dbms_stats.convert_raw_value('5741524E494E475F53455454494E475324', :max_value); end; / print min_value print max_value MIN_VALUE ------------------------------------ ACCESS$ MAX_VALUE ------------------------------------ WARNING_SETTINGS$