Java data type and database data type

on a recent project, I found that all data types of entity classes are strings, no matter what type of oracle database can be inserted and do not need to be converted. Did the bottom layer of jdbc help me convert it?

Sep.06,2021

jdbc should not be converted, just take a look at the sql statement typed in the log.

oralce converts the value of the field when doing insert/select and other operations. If there is no problem with the format of the string, it can be converted to date, number and other types, and the sql statement can be executed normally.

Use caution in

select statements. Indexes are not used when implicit conversions occur.

MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b364ee-2c010.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b364ee-2c010.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
Need Help?