Error
Error Code:
42611
PostgreSQL Error 42611: Invalid Column Definition
Description
Error 42611, 'invalid column definition', indicates a problem with the syntax or rules used when defining a column within a PostgreSQL table. This typically occurs during `CREATE TABLE` or `ALTER TABLE` statements when the column specification is malformed, unrecognized, or violates database constraints.
Error Message
invalid column definition
Known Causes
4 known causesInvalid Data Type Specification
The specified data type for a column is unrecognized, incorrectly formatted, or has invalid length/precision parameters.
Malformed Column Constraints
Constraints such as `NOT NULL`, `DEFAULT`, `PRIMARY KEY`, or `CHECK` are improperly placed or syntactically incorrect within the column definition.
Using Reserved Keywords
A reserved SQL keyword has been used as a column name without being properly quoted, causing a syntax conflict.
Incompatible Default Value
The `DEFAULT` value specified for a column does not match its declared data type or contains a syntax error.
Solutions
3 solutions available1. Correcting Data Type Mismatches easy
Ensure that the data type specified for a column is valid and compatible with the intended data.
1
Review the `CREATE TABLE` or `ALTER TABLE` statement where the error occurred.
2
Identify the column definition that is causing the error. Look for typos or unrecognized data types.
Example of an invalid definition: `my_column VARCHAR(255, 10)` (too many arguments for VARCHAR)3
Consult the PostgreSQL documentation for a list of valid data types and their correct syntax. Common types include `VARCHAR`, `INT`, `BIGINT`, `BOOLEAN`, `DATE`, `TIMESTAMP`, `NUMERIC`, `JSONB`, etc.
4
Correct the data type to a valid PostgreSQL type and ensure it has the correct number of arguments (e.g., `VARCHAR(255)` is valid, `VARCHAR(255, 10)` is not).
Corrected example: `my_column VARCHAR(255)`5
Re-execute the corrected `CREATE TABLE` or `ALTER TABLE` statement.
2. Resolving Constraint Syntax Errors medium
Verify that any constraints (like `NOT NULL`, `UNIQUE`, `PRIMARY KEY`, `FOREIGN KEY`, `CHECK`) are defined with correct PostgreSQL syntax.
1
Examine the column definition and any associated constraints in your SQL statement.
2
Check the syntax for each constraint. For example, `NOT NULL` should be a keyword, not a data type.
Invalid: `my_column INT NOTNULL`
Valid: `my_column INT NOT NULL`3
Ensure that `PRIMARY KEY` and `UNIQUE` constraints are applied correctly, either inline with the column definition or as a table-level constraint.
Inline: `id SERIAL PRIMARY KEY`
Table-level: `CONSTRAINT pk_my_table PRIMARY KEY (id)`4
For `FOREIGN KEY` constraints, verify that the referenced table and column exist and have compatible data types.
Example: `user_id INT REFERENCES users(id)`5
For `CHECK` constraints, ensure the expression is valid SQL and the column names are correct.
Example: `price NUMERIC CHECK (price > 0)`6
Correct any syntax errors in the constraint definitions and re-run the statement.
3. Validating Column Name and Keyword Usage easy
Ensure column names are not reserved keywords and are valid identifiers.
1
Identify the column name causing the error.
2
Check if the column name is a PostgreSQL reserved keyword (e.g., `SELECT`, `FROM`, `WHERE`, `TABLE`, `COLUMN`). A comprehensive list can be found in the PostgreSQL documentation.
3
If the column name is a reserved keyword, enclose it in double quotes to escape it.
Example: `CREATE TABLE my_table ("select" INT);`4
Alternatively, rename the column to a non-reserved keyword for better readability and to avoid quoting issues.
Example: `CREATE TABLE my_table (select_count INT);`5
Also, ensure the column name follows valid identifier rules (e.g., starts with a letter or underscore, can contain letters, numbers, and underscores).
6
Re-execute the statement with the corrected column name or quoting.