oracle 将 CLOB 列更新为 NULL
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Update CLOB Column to NULL
提问by c12
I need to update an oracle clob column value to null. I tried to below but that didn't work. Any ideas?
我需要将一个 oracle clob 列值更新为null. 我试过下面，但没有奏效。有任何想法吗？
update table_name
set CONTENT_TEMPLATE=empty_clob()
where table_key=12345;
Name Null Type
-------------------- -------- -------------
TEST_KEY NOT NULL NUMBER(10)
TEST_ID NOT NULL VARCHAR2(100)
TEST_TYPE NOT NULL VARCHAR2(30)
TEMPLATE_ID VARCHAR2(100)
ROUTE VARCHAR2(100)
MEDIUM VARCHAR2(100)
BEGIN_EFFECTIVE_DATE NOT NULL DATE
END_EFFECTIVE_DATE NOT NULL DATE
CUSTOMER_ID NOT NULL VARCHAR2(30)
VAR_ID NOT NULL VARCHAR2(30)
CREATION_DATE NOT NULL DATE
LAST_UPDATED_DATE NOT NULL DATE
LAST_UPDATED_BY NOT NULL VARCHAR2(30)
CONTENT_TEMPLATE CLOB
SUBJECT_TEMPLATE CLOB
UNIT_TYPE VARCHAR2(30)
OVERLOADED_ALERT_KEY NUMBER(10)
ALERT_TYPE_ALIAS VARCHAR2(100)
回答by AnBisw
update table_name
set column_name = null
where table_key=12345;
NULL- Absense of data
NULL- 数据缺失
empty_clob()- CLOBis initialized and empty, not same as NULL.
empty_clob()-CLOB已初始化且为空，与NULL.
If you still get ORA-01407with this column then that means there is a NOT NULLconstraint on the column which is of CLOBdatatype.
如果您仍然ORA-01407使用此列，则表示该列存在数据类型的NOT NULL约束CLOB。
UPDATE:
更新：
Since the CLOBcolumn is not NOT NULLsetting it to CONTENT_TEMPLATE = NULLshould work. CONTENT_TEMPLATE = empty_clob()will also work, but bear in mind that it is not same as NULL.
由于该CLOB列未NOT NULL将其设置为CONTENT_TEMPLATE = NULL应该可以工作。CONTENT_TEMPLATE = empty_clob()也可以工作，但请记住，它与NULL.
