Oracle 表分区策略

表分析，识别大表

-- 查看最后的统计收集的时间
SELECT
    table_name,
    TO_CHAR(last_analyzed,'YYYY-MM-DD HH24:MI:SS') last_analyzed
FROM
    dba_tables
WHERE
    table_name = 'F_ORDER';

-- 收集统计信息
ANALYZE TABLE f_order COMPUTE STATISTICS;

-- 查看直方图的统计情况
SELECT
    column_name,
    histogram -- 是否有直方图
FROM
    dba_tab_col_statistics
WHERE
    table_name = 'F_ORDER';

-- 统计各个表的大小
SELECT
    tabs.owner,
    tabs.tablespace_name,
    tabs.table_name,
    round(
        SUM(ext.bytes) / 1024 / 1024,
        5
    ) m
FROM
    sys.dba_tables tabs,
    sys.dba_extents ext
WHERE
        tabs.tablespace_name = ext.tablespace_name
    AND
        tabs.owner = upper('finance_dev')
GROUP BY
    tabs.owner,
    tabs.tablespace_name,
    tabs.table_name;