PostgreSQL数组怎么添加元素

# 方式1

postgres=# insert into t_kenyon(items) values('{1,2}');

INSERT 0 1

postgres=# insert into t_kenyon(items) values('{3,4,5}');

INSERT 0 1

# 方式2

postgres=# insert into t_kenyon(items) values(array[6,7,8,9]);

INSERT 0 1

postgres=# select * from t_kenyon;id |   items 

----+-----------

  1 | {1,2}

  2 | {3,4,5}

  3 | {6,7,8,9}

(3 rows)

postgres=# delete from t_kenyon where id = 3;

DELETE 1

postgres=# delete from t_kenyon where items[1] = 4;

DELETE 0

postgres=# delete from t_kenyon where items[1] = 3;

DELETE 1

# 往后追加

postgres=# update t_kenyon set items = items||7;

UPDATE 1

postgres=# select * from t_kenyon;id |  items

----+---------

  1 | {1,2,7}

(1 row)

postgres=# update t_kenyon set items = items||'{99,66}';

UPDATE 1

postgres=# select * from t_kenyon;

id |      items     

----+------------------

  1 | {1,2,7,55,99,66}

(1 row)

# 往前插

postgres=# update t_kenyon set items = array_prepend(55,items) ;

UPDATE 1

postgres=# select * from t_kenyon;

id |        items      

----+---------------------

  1 | {55,1,2,7,55,99,66}

(1 row)