PostgreSQL - ALTER 列数据类型从整数到整数数组
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PostgreSQL - ALTER column data type from integer to integer array
提问by srchalikonda
Kindly help to modify a column of type integer to integer array:
请帮助将整数类型的列修改为整数数组：
I had created a table with a column content_idof type integer. then I tried to change the content_id(integer)to integer[](integer array)but its showing error as displayed:
我创建了一个包含content_id整数类型列的表。然后我尝试将其更改content_id(integer)为integer[](integer array)但其显示错误如下所示：
TestDatabase=# ALTER TABLE tbl_handset_content ALTER COLUMN content_id TYPE integer[];
ERROR: column "content_id" cannot be cast to type "pg_catalog.int4[]"
Regards,
问候，
Sravan
斯拉文
回答by Wojtas
Try this (column test_id is of type INTEGER before alter takes place). PostgreSQL 8.4.
试试这个（在改变发生之前，列 test_id 是 INTEGER 类型）。PostgreSQL 8.4。
ALTER TABLE test.test_id
ALTER COLUMN test_id TYPE INTEGER[]
USING array[test_id]::INTEGER[];
回答by Fotoncito
This worked better for me!
这对我来说效果更好！
ALTER TABLE schema.table
ALTER COLUMN column
DROP DEFAULT;
ALTER TABLE schema.table
ALTER COLUMN column TYPE INTEGER[]
USING array[column]::INTEGER[];
ALTER TABLE schema.table
ALTER COLUMN column SET DEFAULT '{}';
