我可以使用什么 SQL 服务器函数来获取 nvarchar(max) 列的字符或字节长度？
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What SQL-server function can I use to get the character or byte length of a nvarchar(max) column?
提问by Jim
I have a column which is of type nvarchar(max). How do I find the length of the string (or the number of bytes) for the column for each row in the table?
我有一个 nvarchar(max) 类型的列。如何找到表中每一行的列的字符串长度（或字节数）？
回答by Brian R. Bondy
SELECT LEN(columnName) AS MyLength FROM myTable
SELECT LEN(columnName) AS MyLength FROM myTable
回答by Joseph Pecoraro
If you want to find out the max there should be a way for you to get the schema of the table. Normally you can do something like SHOW COLUMNSin SQL or a DESCRIBEstyle command. In a mysql shell that can be shortened to:
如果您想找出最大值，应该有一种方法可以让您获得表的架构。通常，您可以在 SQL 中执行SHOW COLUMNS或DESCRIBE样式命令之类的操作。在可以缩短为的 mysql shell 中：
desc tablename;
Then if you want to determine the length of a string there is normally a function like LENGTH(for bytes)or CHAR_LENGTH(for characters).
然后，如果您想确定字符串的长度，通常有一个函数，如LENGTH （用于字节）或CHAR_LENGTH （用于字符）。
SELECT *, LENGTH(fieldname) AS len FROM tablename
回答by sivasankar
SELECT LEN(columnName) AS MyLength FROM myTable
I used this query for my table. It displays the size of each row in a particular column.
我将此查询用于我的表。它显示特定列中每一行的大小。
I need that field name size maximum it allow the characters.
我需要该字段名称的最大大小，它允许字符。
