DBMS_LOB.SUBSTR(SUBSTR(CLOB,1,2048)) DBMS_LOB.SUBSTR() 会将 clob转为 varchar2,而varchar2是有长度限制的,4K(存储过程里是32767)
LOB数据类型通常用于存储大量的文本、图像或音频数据。在处理这些数据类型时,需要使用专门的方法来提取和操作其中的部分数据。dbms_lob.substr就是用于从LOB字段中提取指定长度的数据的函数。 二、使用方法 1. 参数说明 在使用dbms_lob.substr函数时,需要传入以下参数: - lob_loc:表示LOB字段或者变量的值。 - ...
According to the dbms_lob.substr documentation, I should be able to use a value in the 2nd parameter up to 32767, and the size of the report is over 200,000 bytes, so it is within the range. After playing with the number, I have found that the make value that I can use in t...
position :=dbms_lob.instr(source_lob, pattern, start_location, nth_occurrence); dbms_output.put_line('The first occurrence starts at position:'||position);selectclob_locatorintosource_lobfrommylobswherelob_index=5; buffer :=dbms_lob.substr(source_lob,9, start_location); dbms_output.put_line...
1、通过dbms_lob.substr()转换clob字段为varchar2类型 在查询dba_stat_extensions视图的时候,其中extension字段是clob类型,直接通过select语句无法显示,如下: 需要通过dbms_lob.substr()转换 SELECT owner ,a.table_name,trim(dbms_lob.substr(extension,4000)) as extension FROM dba_stat_extensions a 转换后显示如...
select DBMS_LOB.SUBSTR(a.COMMENTS, 3998, 1) FROM FOO; 我收到错误: “ORA-06502:PL/SQL:数字或值错误:字符串缓冲区太小” . 问题出在特殊字符上。每个新的特殊字符需要 8 个字节,所以当我将字符串限制减少到 3992 时,它就可以工作了。 DBMS_LOB.SUBSTR(a.COMMENTS, 3992, 1) works. ...
dbms_lob.substr( lob_loc in clob character set any_cs, amount in integer := 32767, offset in integer := 1) return varchar2 character set lob_loc%charset; 其中各个参数的含义如下: lob_loc是substr函数要操作的大型对象定位器 amount是要从大型对象中抽取的字节数 ...
SELECT DBMS_LOB.SUBSTR(CSUSERATTACHEDFILE01.FILECONTENT, 3, 4) AS blobSubstring FROM CSUSERATTACHEDFILE CSUSERATTACHEDFILE01 WHERE (CSUSERATTACHEDFILE01.CSUSERATTACHEDFILENO=10291) XML query API Copy <query alias="testLobSubString" projectedClass="com.taleo.akirademo.entity.AttachedFile"> <projectio...
比较2 个 LOB 的数据,返回一个结果值。 语法如下: FUNCTION COMPARE( LOB_1 IN BLOB, LOB_2 IN BLOB, AMOUNT IN BIGINT:= DBMS_LOB.LOBMAXSIZE, OFFSET_1 IN BIGINT := 1, OFFSET_2 IN BIGINT := 1 ) RETURN INTEGER; FUNCTION COMPARE( LOB_1 IN CLOB, LOB_2 IN CLOB, AMOUNT IN BIGINT:...