Oracle 将字符插入字符串
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Oracle insert character into a string
提问by user1761160
I have this table of rows
我有这个行表
RowA
______
ABC123
DEF432
WER677
JKL342
how can I add a '_' in between the record using oracle to this? Assuming to add on the last 4 character.
如何使用 oracle 在记录之间添加“_”？假设添加最后 4 个字符。
RowA
______
ABC_123
DEF_432
WER_677
JKL_342
回答by M. Abbas
You would try something like:
你会尝试这样的事情：
Update Table_name set table_column = substr(table_column, 1, 3) || '_' || substr(table_column, 4);
The SUBSTRfunctions allows you to extract a substring from a string.
The syntax for the SUBSTRfunction is:
这些SUBSTR函数允许您从字符串中提取子字符串。该SUBSTR函数的语法是：
SUBSTR( string, start_position, [ length ] )
stringis the source string.
string是源字符串。
start_positionis the position for extraction. The first position in the string is always 1.
start_position是提取位置。字符串中的第一个位置始终为 1。
lengthis optional. It is the number of characters to extract. If this parameter is omitted, the SUBSTR function will return the entire string.
length是可选的。它是要提取的字符数。如果省略此参数，SUBSTR 函数将返回整个字符串。
回答by Nick Krasnov
Another approach, using regexp_replace()regular expression function:
另一种方法，使用regexp_replace()正则表达式函数：
select regexp_replace(RowA, '^([[:alpha:]]{3})', '_') as res
from your_table
Result:
结果：
RES
----------
ABC_123
DEF_432
WER_677
JKL_342
