Summary of Oracle error codes and their meanings

Oracle database is one of the most popular relational database management systems in the world. In the process of using Oracle database, various error codes are often encountered. These error codes provide useful information to help determine the nature of the problems and resolve them.

In this article, we will discuss some common error codes and their meanings in Oracle database. Hopefully this article will help readers better understand these errors so that they can quickly diagnose and fix problems when they encounter them.

1. ORA-00001: Violation of unique constraint

ORA-00001 error code is an error that occurs when a unique constraint is violated. In Oracle database, unique constraints are set on one or more columns in the data table, and the values ​​of these columns must be unique.

If duplicate unique values ​​appear when inserting or updating data, the ORA-00001 error code will occur. This is usually caused by existing data not being taken into account during insert or update operations.

2. ORA-00904: Invalid identifier

ORA-00904 error code indicates that an invalid column name or object name was specified in the SQL statement. This is usually caused by a typographical error or by defining a non-existing table or column for the Oracle database.

This error should be easy to resolve, just confirm the correct name of the table or column and make sure the correct object name is entered in the SQL statement.

3. ORA-01017: Invalid username/password; login denied

ORA-01017 error code indicates that an invalid username was entered when trying to connect to the Oracle database or password. This error is usually caused by entering a non-existent or incorrect username or password.

To resolve this error, you need to confirm that the username and password you entered are correct. If you are not sure, you can contact the Oracle database administrator for verification.

4. ORA-01034: ORACLE is not available

ORA-01034 error code means that the Oracle instance cannot be connected. This is usually caused by the Oracle instance not running or not starting correctly.

To resolve this error, you need to ensure that the Oracle database instance is running and that the instance name is correctly specified in the connection string.

5. ORA-01722: Invalid number

ORA-01722 error indicates that a non-numeric value was specified in the SQL statement when Oracle expected a numeric value. This error is usually caused by incorrect formatting or wrong type when entering or importing data.

The easiest way to handle the ORA-01722 error is to ensure that the input or imported data is in the correct format and that the data types are handled correctly.

6. ORA-01400: Unable to insert (or update) NULL into (SYS). .

ORA-01400 error code indicates an attempt to insert a NULL value into a non-null column. This is usually caused by columns that require a non-NULL value to be inserted and are forced to be assigned a NULL value.

To resolve this error, you need to check the inserted or updated data to confirm that NULL values ​​are not used to fill the disallowed columns.

Summary

Error codes in Oracle database provide useful information to help identify problems and resolve them. The above introduces some common Oracle error codes. You can quickly locate the cause of the problem based on these error codes and take corresponding measures to solve them. However, when troubleshooting issues related to Oracle error codes, you need to take care to check all available information in order to diagnose and solve the problem as accurately as possible.

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