Troubleshooting SQLite Result Codes from Error 517 to 531

SQLServerF1

SQL return code 517 SQLITE_BUSY_SNAPSHOT
The SQLITE_BUSY_SNAPSHOT error code is an extended error code for SQLITE_BUSY that occurs on WAL mode databases when a database connection tries to promote a read transaction into a write transaction but finds that another database connection has already written to the database and thus invalidated prior reads.
The following scenario illustrates how an SQLITE_BUSY_SNAPSHOT error might arise:
Process A starts a read transaction on the database and does one or more SELECT statement. Process A keeps the transaction open.
Process B updates the database, changing values previous read by process A.

Process A now tries to write to the database. But process A’s view of the database content is now obsolete because process B has modified the database file after process A read from it. Hence process B gets an SQLITE_BUSY_SNAPSHOT error.
SQL return code 520 SQLITE_READONLY_CANTLOCK
The SQLITE_READONLY_CANTLOCK error code is an extended error code for SQLITE_READONLY. The SQLITE_READONLY_CANTLOCK error code indicates that SQLite is unable to obtain a read lock on a WAL mode database because the shared-memory file associated with that database is read-only.

SQL return code 522 SQLITE_IOERR_SHORT_READ
The SQLITE_IOERR_SHORT_READ error code is an extended error code for SQLITE_IOERR indicating that a read attempt in the VFS layer was unable to obtain as many bytes as was requested. This might be due to a truncated file.
SQL return code 526 SQLITE_CANTOPEN_ISDIR
The SQLITE_CANTOPEN_ISDIR error code is an extended error code for SQLITE_CANTOPEN indicating that a file open operation failed because the file is really a directory.
SQL return code 531 SQLITE_CONSTRAINT_COMMITHOOK
The SQLITE_CONSTRAINT_COMMITHOOK error code is an extended error code for SQLITE_CONSTRAINT indicating that a commit hook callback returned non-zero that thus caused the SQL statement to be rolled back.

Above are the list of SQLite Result Codes or Error Codes and their Description from Error 517 to 531 while performing certain operations against SQLite.

What are SQLite Errors?

SQLite programs have access to several types of common error information when the server returns an error. The SQLite message displayed contains three types of information:

A numeric error code. This number is SQLite and is not portable to other database systems. All result codes are integers. Symbolic names for all result codes are created using “#define” macros.Primary result code symbolic names are of the form “SQLITE_XXXXXX” where XXXXXX is a sequence of uppercase alphabetic characters. Extended result code names are of the form “SQLITE_XXXXXX_YYYYYYY” where the XXXXXX part is the corresponding primary result code and the YYYYYYY is an extension that further classifies the result code. The names and numeric values for existing result codes are fixed and unchanging. However, new result codes, and especially new extended result codes, might appear in future releases of SQLite.

Hope this was helpful.

Thanks,
SQLServerF1 Team
Information about SQLite Result Codes or Error Codes and Error Messages or Warnings on Windows, Linux Operating Systems.

 

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