Question

TL; DR

my_base=# SELECT *, pg_size_pretty(total_bytes) AS total
    , pg_size_pretty(index_bytes) AS INDEX
    , pg_size_pretty(toast_bytes) AS toast
    , pg_size_pretty(table_bytes) AS TABLE
  FROM (
  SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM (
      SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME
              , c.reltuples AS row_estimate
              , pg_total_relation_size(c.oid) AS total_bytes
              , pg_indexes_size(c.oid) AS index_bytes
              , pg_total_relation_size(reltoastrelid) AS toast_bytes
          FROM pg_class c
          LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
          WHERE relkind = 'r' and relname = 'my_table'
  ) a
) a;
-[ RECORD 1 ]+----------------
oid          | 24116771
table_schema | public
table_name   | my_table
row_estimate | 0
total_bytes  | 13250125824
index_bytes  | 2306334720
toast_bytes  | 8192
table_bytes  | 10943782912
total        | 12 GB
index        | 2199 MB
toast        | 8192 bytes
table        | 10 GB

这怎么可能？

其余的......

大家好。

我必须在我的工作站上导入一个巨大的转储文件（12 Go）。我通过以下命令创建了这个转储文件：

pg_dump -U my_user -d my_base --data-only --table=my_table  > my_table.sql

然后我在我的工作站上导入了转储文件：

psql -U my_base -f my_table.sql

1小时后，导入完成，输出如下：

SET
SET
SET
SET
SET
SET
SET
















psql:my_table.sql:23308453: ERROR:  Insert or update on table "my_table" violates custom foreign key trigger my_other_table_id_my_table_fk_" 
DETAILS : Key (my_other_table_id = 474804) is not present in my_other_table
CONTEXT : COPY my_table, line 23118758: "... data ..."
  setval  
----------
 23354338
(1 line)

根据我的理解，错误应该只是导入跳过文件的行。导入后，我的表已经增长，但它不包含任何行：

my_base=# SELECT *, pg_size_pretty(total_bytes) AS total
    , pg_size_pretty(index_bytes) AS INDEX
    , pg_size_pretty(toast_bytes) AS toast
    , pg_size_pretty(table_bytes) AS TABLE
  FROM (
  SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM (
      SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME
              , c.reltuples AS row_estimate
              , pg_total_relation_size(c.oid) AS total_bytes
              , pg_indexes_size(c.oid) AS index_bytes
              , pg_total_relation_size(reltoastrelid) AS toast_bytes
          FROM pg_class c
          LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
          WHERE relkind = 'r' and relname = 'my_table'
  ) a
) a;
-[ RECORD 1 ]+----------------
oid          | 24116771
table_schema | public
table_name   | my_table
row_estimate | 0
total_bytes  | 13250125824
index_bytes  | 2306334720
toast_bytes  | 8192
table_bytes  | 10943782912
total        | 12 GB
index        | 2199 MB
toast        | 8192 bytes
table        | 10 GB

如果没有添加任何数据，我的桌子怎么会增长？几个小时后（我让我的工作站在夜间运行），我有以下结果（我猜autovacuum发挥了它的魔力）：

my_base=# SELECT *, pg_size_pretty(total_bytes) AS total
    , pg_size_pretty(index_bytes) AS INDEX
    , pg_size_pretty(toast_bytes) AS toast
    , pg_size_pretty(table_bytes) AS TABLE
  FROM (
  SELECT *, total_bytes-index_bytes-COALESCE(toast_bytes,0) AS table_bytes FROM (
      SELECT c.oid,nspname AS table_schema, relname AS TABLE_NAME
              , c.reltuples AS row_estimate
              , pg_total_relation_size(c.oid) AS total_bytes
              , pg_indexes_size(c.oid) AS index_bytes
              , pg_total_relation_size(reltoastrelid) AS toast_bytes
          FROM pg_class c
          LEFT JOIN pg_namespace n ON n.oid = c.relnamespace
          WHERE relkind = 'r' and relname = 'my_table'
  ) a
) a;
-[ RECORD 1 ]+----------------
oid          | 24116771
table_schema | public
table_name   | my_table
row_estimate | 0
total_bytes  | 2306359296
index_bytes  | 2306334720
toast_bytes  | 8192
table_bytes  | 16384
total        | 2200 MB
index        | 2199 MB
toast        | 8192 bytes
table        | 16 kB

有人知道这里发生了什么吗？

导入的转储使表没有行

0 个答案: