Today in order to modify the database configuration, the sga_max_size set to 20G, but Sga_target did not change, still for 10G results after the restart of the database will not start, reported ORA-00821 error ora-00821:specified value of Sga_target * * are too small, needs to being at least * * and directly alter system set SGA_TARGET=20800M is not possible, because the database has not been started, there is no way to directly modify the database parameters, So you can only manually modify the SPFile file to modify the startup parameters, the workaround is as follows: 1. Go to $oracle_home\bin directory CD D:\Oracle\App\product\11.2.0\dbhome_1\BIN 2. Execute Sqlplus/as SYSDBA 3. Execute create Pfile from SPFile, generate Pfile file according to SPFile file, here is D:\Oracle\App\product\11.2.0\dbhome_1\database\ Initc2.ora 4. Edit the Initc2.ora file to change the Sga_target assignment to the same as Sga_max_size 5. Execute create SPFile from Pfile, and turn the modified file back to 6. Start the database with startup and get it done
Oracle Initial parameter setting error causes the database to fail to start the ORA-00821 solution
