我的团队采用了层层嵌套的视图,因此经常使用DROP TABLE CASCADE
会导致灾难性后果和很多的试错。
我想要的是一条查询语句,能够返回给定schema
和table
的所有依赖对象,并按正确的顺序重新创建它们,这样它们就可以被自动化并在脚本中运行。我正在使用修改版的Redshift DROP TABLE
文档上的依赖性查询http://docs.aws.amazon.com/redshift/latest/dg/r_DROP_TABLE.html。
它似乎只返回视图及其依赖关系,而不是普通表。我感觉离成功不远了,我漏掉了什么?
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