jdbcTemplate的setMaxRows如何工作

Question

I am trying to understand the way ' setMaxRows ' method of JdbcTemplate works. Suppose I have a database table named ' employee ' which has 10 records.

I set maxRows to 5 using JdbcTemplate.setMaxRows(5) .

Now I do a select using following statement,

jdbcTemplate.queryForRowSet("select * from employee");

Above statement rightly returns 5 records, but when I have a look at the database logs the query executed there is " select * from employee ", without any limit clause.

So after setting maxRows to 'n' does jdbcTemplate fecthes all records from ' employee ' table and then returns only 'n' rows. Or it fetches only 'n' records from database?

Answer 1

How the maximum number of rows is handled depends on the JDBC driver. The value of maxRows is eventually being set on the created Statement through the corresponding setMaxRows method. What your driver does with that is up to the driver.

The JdbcTemplate merely passes it on.