查询以查找 Oracle SQL 中各种 SCHEMAS 占用的表大小（以 GB 为单位）

Question

我试图在 Oracle DB 中找到被表列表占用的 space（对于各种 SCHEMAS），目前我正在使用这个查询

查询 1 - DBA_SEGMENTS

SELECT SEGMENT_NAME,SUM (BYTES)/1024/1024/1024 AS GB,
ROUND(100*RATIO_TO_REPORT(GB) OVER (), 4) PERCENTAGE  
FROM DBA_SEGMENTS
WHERE OWNER='SCHEMA_NAME'
AND SEGMENT_TYPE ='TABLE'
AND SEGMENT_NAME
IN
(
'LIST OF TABLES'
)
GROUP BY SEGMENT_NAME,BYTES
ORDER BY GB DESC;

查询 2 - DBA_OBJECTS

SELECT DISTINCT OBJECT_NAME FROM DBA_OBJECTS
WHERE OWNER='SCHEMA'
AND OBJECT_NAME IN 
(
'LIST OF TABLES'
)
GROUP BY OBJECT_NAME
ORDER BY OBJECT_NAME;

当我比较 LIST OF TABLES 计数时它不匹配，可能是什么原因？

你能否建议这是正确的还是有更好的方法来实现这个？

参考 https://serverfault.com/questions/132620/oracle-how-to-find-out-storage-space-used-by-a-table

附加查询 1

SET SERVEROUTPUT ON;
DECLARE
  input_owner         NVARCHAR2(128) := 'SCHEMA_NAME';
  segment_size_blocks NUMBER;
  segment_size_bytes  NUMBER;
  used_blocks         NUMBER;
  used_bytes          NUMBER;
  expired_blocks      NUMBER;
  expired_bytes       NUMBER;
  unexpired_blocks    NUMBER;
  unexpired_bytes     NUMBER;
  total_blocks        NUMBER;
  total_bytes         NUMBER;
  unused_blocks       NUMBER;
  unused_bytes        NUMBER;
  last_ext_file_id    NUMBER;
  last_ext_blk_id     NUMBER;
  last_used_blk       NUMBER;
  result_table        NVARCHAR2(128);
  result_segment_type NVARCHAR2(128);
  result_used_mb      NUMBER;
  result_unused_mb    NUMBER;
  result_total_mb     NUMBER;
  CURSOR cur
  IS
    SELECT
      s.segment_name   AS segment_name,
      s.owner          AS segment_owner,
      s.partition_name AS partition_name,
      s.segment_type   AS segment_type,
      CASE WHEN s.segment_type IN ('TABLE', 'TABLE PARTITION', 'TABLE SUBPARTITION')
        THEN s.segment_name
      WHEN s.segment_type IN ('INDEX', 'INDEX PARTITION', 'INDEX SUBPARTITION')
        THEN (SELECT i.table_name
              FROM dba_indexes i
              WHERE s.segment_name = i.index_name AND s.owner = i.owner)
      WHEN s.segment_type IN ('LOBSEGMENT', 'LOB PARTITION')
        THEN (SELECT l.table_name
              FROM dba_lobs l
              WHERE s.segment_name = l.segment_name AND s.owner = l.owner)
      WHEN s.segment_type IN ('LOBINDEX')
        THEN (SELECT l.table_name
              FROM dba_lobs l
              WHERE s.segment_name = l.index_name AND s.owner = l.owner)
      ELSE 'Unknown'
      END              AS table_name,
      s.bytes          AS segment_bytes
    FROM dba_segments s
    WHERE owner = input_owner
    and segment_name in 
    (

    )
    ORDER BY table_name, segment_type;
BEGIN
  dbms_output.put_line('table                         ; segment type        ;   used (mb)     ; unused (mb)     ;  total (mb)');

  FOR ro IN cur
  LOOP

    result_table := ro.table_name;
    result_segment_type := ro.segment_type;

    IF ro.segment_type IN ('TABLE', 'INDEX')
    THEN
      dbms_space.unused_space(
          segment_owner             => ro.segment_owner,
          segment_name              => ro.segment_name,
          segment_type              => ro.segment_type,
          total_blocks              => total_blocks,
          total_bytes               => total_bytes,
          unused_blocks             => unused_blocks,
          unused_bytes              => unused_bytes,
          last_used_extent_file_id  => last_ext_file_id,
          last_used_extent_block_id => last_ext_blk_id,
          last_used_block           => last_used_blk);

      result_used_mb := (total_bytes - unused_bytes) / 1024 / 1024;
      result_unused_mb := unused_bytes / 1024 / 1024;
      result_total_mb := total_bytes / 1024 / 1024;

    ELSIF ro.segment_type IN ('LOBSEGMENT')
    THEN
      dbms_space.space_usage(
          segment_owner           => ro.segment_owner,
          segment_name            => ro.segment_name,
          segment_type            => 'LOB',
          partition_name          => ro.partition_name,
          segment_size_blocks     => segment_size_blocks,
          segment_size_bytes      => segment_size_bytes,
          used_blocks             => used_blocks,
          used_bytes              => used_bytes,
          expired_blocks          => expired_blocks,
          expired_bytes           => expired_bytes,
          unexpired_blocks        => unexpired_blocks,
          unexpired_bytes         => unexpired_bytes
      );
      result_used_mb := used_bytes / 1024 / 1024;
      result_unused_mb := (segment_size_bytes - used_bytes) / 1024 / 1024;
      result_total_mb := segment_size_bytes / 1024 / 1024;
    ELSE
      -- TODO ??
      result_used_mb := ro.segment_bytes / 1024 / 1024;
      result_unused_mb := 0;
      result_total_mb := result_used_mb + result_unused_mb;
    END IF;

    dbms_output.put_line(
        RPAD(result_table, 30) || '; ' ||
        RPAD(result_segment_type, 20)|| '; ' ||
        TO_CHAR(result_used_mb  / 1024 / 1024, '999999999990D00')|| '; ' ||
        TO_CHAR(result_unused_mb  / 1024 / 1024, '999999999990D00')|| '; ' ||
        TO_CHAR(result_total_mb / 1024 / 1024, '999999999990D00'));
  END LOOP;
END;

附加查询 2

WITH DA AS (
 SELECT OWNER, SEGMENT_NAME, SUM(BYTES)/1024/1024 SIZE_MB
   FROM DBA_EXTENTS
   GROUP BY ROLLUP(OWNER, SEGMENT_NAME)
) SELECT OWNER, SEGMENT_NAME, SIZE_MB, ROUND(SIZE_MB/TOTAL_MB*100)
  FROM DA 
    CROSS JOIN (
      SELECT SIZE_MB AS TOTAL_MB 
      FROM DA T WHERE OWNER IS NULL AND SEGMENT_NAME IS NULL
    )
ORDER BY SIZE_MB DESC

Answer 1

这是一个相当准确的查询，它将表、索引和任何分区 tables/indexes 考虑到单个架构所有者的所有表。请注意，由于块大小、文件头等原因，实际使用的 space 会有一些额外的开销

  select segment_name
         , segment_type
         , sum(bytes)/1024/1024/1024 as GB
         , ROUND(100*RATIO_TO_REPORT(bytes) OVER (), 4) PERCENTAGE
  from dba_segments ds
  where
      owner ='SCOTT'
      and (
              segment_type like 'TABLE%'
              and segment_name in ('EMP', 'SALGRADE', 'EMP_BKP', 'DEPT')
          or
              (
                 segment_type like 'INDEX%'
                 and segment_name in (
                         select index_name from dba_indexes di
                             where owner ='SCOTT'
                               and di.table_name in ('EMP', 'SALGRADE', 'EMP_BKP', 'DEPT')
                         )
              -- more fun here for LOBs, etc.
             )
         )
  group by segment_name, segment_type, bytes
  order by GB desc;

查看 DBA_LOBS 以了解要添加到 -- more fun here 以获取 LOB 信息的其他条件。

查询以查找 Oracle SQL 中各种 SCHEMAS 占用的表大小（以 GB 为单位）

Query to find the tables size occupied in GB in Oracle SQL for various SCHEMAS

sql

oracle

sum

database-administration