All Errors

RAISE EXCEPTION is a PL/pgSQL statement for throwing custom errors in stored procedures and functions. Understanding proper syntax and usage prevents compilation errors and ensures transactions abort correctly when validation fails.

This error occurs when PostgreSQL cannot find a specified role (user account) in the database. It commonly happens during initial setup when the default postgres role hasn't been created, or when referencing a role that was never created or was accidentally dropped.

This error occurs when PostgreSQL rejects a login attempt due to incorrect credentials, misconfigured authentication settings, or missing passwords. Verify your credentials and pg_hba.conf configuration to resolve it.

This error occurs when you try to set a Redis key with an invalid expiration time, typically because the expire duration is negative, zero, or overflowed. Learn how to fix this common SET command issue.

PL/pgSQL errors occur when stored procedures, functions, or triggers contain syntax errors, type mismatches, or runtime exceptions. Fix them by validating RAISE statement syntax, checking parameter counts, and using GET STACKED DIAGNOSTICS for debugging.

PostgreSQL is warning that autovacuum has fallen behind in freezing old transaction IDs. This warning appears when the database is approaching transaction ID wraparound. You must run VACUUM soon to freeze old rows and prevent data corruption.

PostgreSQL enters read-only mode when transaction ID (XID) wraparound is imminent to prevent data corruption. This happens when autovacuum falls behind freezing old transactions, and you must run VACUUM immediately to restore write access before data loss occurs.

This PostgreSQL error occurs when a column definition specifies invalid length, precision, or scale attributes. Common causes include incorrect VARCHAR lengths, incompatible numeric precision/scale combinations, and invalid constraint specifications.

PostgreSQL extensions must have their supporting files installed on the system before you can use CREATE EXTENSION to load them into a database. This error occurs when the extension control file is missing or the extension package is not installed.

Foreign data wrapper (FDW) errors occur when connecting to remote data sources. Common causes include missing extensions, misconfigured servers, invalid credentials, or missing handler functions. Fix by installing postgres_fdw, verifying server configuration, and ensuring proper user mappings.

The "ERR EXEC without MULTI" error occurs when attempting to execute EXEC without first starting a transaction with MULTI. This is typically caused by connection switching, premature DISCARD calls, or connection pool issues in client libraries.

The PostgreSQL "syntax error at or near UNION" occurs when a UNION query is malformed, typically due to ORDER BY or LIMIT clauses appearing before UNION, mismatched column counts, incompatible data types, or missing parentheses around subqueries. Fixing requires understanding proper UNION syntax and ensuring all SELECT statements match in structure.

This error occurs when PostgreSQL cannot find a required extension. The extension files may not be installed, or they are not available in the system. Most commonly, you need to install the extension using CREATE EXTENSION or ensure the required packages are installed on your system.

Redis "ERR syntax error" occurs when a command violates the Redis Serialization Protocol (RESP) format or uses incorrect command syntax. This typically happens with malformed commands, wrong argument counts, or protocol violations.

A foreign key constraint violation occurs when you try to insert, update, or delete a row that breaks the relationship between parent and child tables. The fix depends on whether you're inserting orphaned records, deleting referenced rows, or loading data in the wrong order.

PostgreSQL "Could not connect to server: No such file or directory" occurs when the client cannot find the Unix domain socket file needed to connect locally. Common causes include PostgreSQL not running, mismatched socket paths between client and server, permission issues, or leftover postmaster.pid files blocking startup. Fixing requires restarting the server, verifying socket locations, and checking permissions.

The pg_dump utility lost its database connection mid-backup, usually due to network issues, server restarts, or timeout settings. Check server status, verify network connectivity, and adjust timeout parameters.

The "FATAL: Ident authentication failed for user" error occurs when PostgreSQL cannot authenticate a connection using ident authentication. This happens when the OS username does not map to the requested database user, or the ident server is unavailable. Fixing requires either switching to password authentication in pg_hba.conf or configuring proper user mappings in pg_ident.conf.

PostgreSQL "permission denied for schema" error occurs when a user lacks necessary privileges to access or create objects within a schema. Especially common in PostgreSQL 15+ where public schema permissions changed, it requires granting explicit USAGE and CREATE privileges. Fix by using GRANT statements with appropriate permissions.

This error occurs when a SQL query references a column that PostgreSQL cannot find in the table or view being queried. Common causes include case sensitivity issues with quoted column names, typos, using column aliases incorrectly, or missing table joins.