Postgres 拒绝将时间戳值从一个 table 插入到另一个 table

Question

Table 富:

create table table_foo
(
    foo_id            integer,
    foo_some_timestamp timestamp without timezone
)

Table栏：

create table table_bar
(
    bar_id            integer,
    foo_id            integer,
    bar_some_timestamp timestamp without timezone
)

当我像这样插入时，它失败了：

insert into table_bar (foo_id, bar_some_timestamp) (
  select foo_id, foo_some_timestamp as bar_some_timestamp
  from foo
  left join table_bar on table_foo.foo_id = table_bar.foo_id
);

但是我得到一个错误：

column "foo_sime_timestamp" is of type timestamp without time zone but expression is of type text Hint: You will need to rewrite or cast the expression.

我试过 to_timestamp 奇怪地抛出以下错误：

to_timestamp(foo_some_timestamp, 'YYYY-MM-DD HH24-MI-SS.US')::timestamp without time zone as bar_some_timestamp

 ERROR: function to_timestamp(timestamp without time zone, unknown) does not exist Hint: No function matches the given name and argument types. You might need to add explicit type casts.

由于是左连接，结果包含很多空值。但是使用 COALESCE 会产生相同的错误。

我错过了什么？ (Postgres v11)

Answer 1

您的目标 table 有三列，但您的 select 只提供了两列。您应该始终限定 INSERT 语句中的目标列，但如果您提供的少于目标 table 的列，则这是强制性的。列按位置匹配，而不是按名称匹配。

insert into table_bar (foo_id, bar_some_timestamp)
select tf.foo_id, tf.foo_some_timestamp
from table_foo tf
  left join table_bar tb on tf.foo_id = tb.foo_id
;

Online example

Postgres 拒绝将时间戳值从一个 table 插入到另一个 table

Postgres refuses to insert timestamp value from one table to another table

postgresql

timestamp-with-timezone