小编典典

如何在Redshift中为对象创建依赖项列表?

sql

我的团队的观点是建立在观点基础之上的,因此通常DROP TABLE CASCADE是灾难的根源和大量的反复试验。

我想是一个查询,返回了需要在给予一定按照正确的顺序重新创建的所有依赖的对象schema,并table让他们可以自动化和运行了一个脚本。我正在使用RedshiftDROP TABLE文档http://docs.aws.amazon.com/redshift/latest/dg/r_DROP_TABLE.html上的依赖项查询的修改版本。

它似乎是在返回视图及其依赖关系,但不是常规表。我感觉自己接近了,我想念什么?

WITH dependencies AS (
    SELECT DISTINCT
      cls1.oid     AS tbloid,
      nsp1.nspname AS schemaname,
      cls1.relname AS name,
      nsp2.nspname AS refbyschemaname,
      cls2.relname AS refbyname,
      cls2.oid     AS viewoid
    FROM pg_catalog.pg_class cls1
      JOIN pg_catalog.pg_depend dep1
        ON cls1.relfilenode = dep1.refobjid
      JOIN pg_catalog.pg_depend dep2
        ON dep1.objid = dep2.objid
      JOIN pg_catalog.pg_class cls2
        ON dep2.refobjid = cls2.relfilenode
      LEFT OUTER JOIN pg_namespace nsp1
        ON cls1.relnamespace = nsp1.oid
      LEFT OUTER JOIN pg_namespace nsp2
        ON cls2.relnamespace = nsp2.oid
    WHERE dep2.deptype IN ('i' :: "CHAR", 'n' :: "CHAR")
          AND cls2.relkind IN ('v' :: "CHAR", 'r' :: "CHAR")
          AND nsp1.nspname NOT IN ('pg_catalog', 'information_schema')
    ORDER BY 4, 5
),

    joined_to_views AS (
      SELECT
        d.schemaname,
        d.name,
        d.refbyschemaname,
        d.refbyname,
        p.definition
      FROM dependencies d
        LEFT JOIN pg_views p
          ON d.refbyschemaname = p.schemaname AND d.refbyname = p.viewname
  )

SELECT *
FROM joined_to_views

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2021-05-16

共1个答案

小编典典

这对您有用吗?

SELECT dependent_ns.nspname as dependent_schema
, dependent_view.relname as dependent_view 
, source_ns.nspname as source_schema
, source_table.relname as source_table
, pg_attribute.attname as column_name
FROM pg_depend 
JOIN pg_rewrite ON pg_depend.objid = pg_rewrite.oid 
JOIN pg_class as dependent_view ON pg_rewrite.ev_class = dependent_view.oid 
JOIN pg_class as source_table ON pg_depend.refobjid = source_table.oid 
JOIN pg_attribute ON pg_depend.refobjid = pg_attribute.attrelid 
    AND pg_depend.refobjsubid = pg_attribute.attnum 
JOIN pg_namespace dependent_ns ON dependent_ns.oid = dependent_view.relnamespace
JOIN pg_namespace source_ns ON source_ns.oid = source_table.relnamespace
WHERE 
source_ns.nspname = 'my_schema'
AND source_table.relname = 'my_table'
AND pg_attribute.attnum > 0 
AND pg_attribute.attname = 'my_column'
ORDER BY 1,2;

如果我做出了错误的假设,请发表评论,然后重新调整我的回答。

2021-05-16