Common SQL Errors and How to Fix Them
Browse all documented SQL errors with detailed explanations, root causes, and step-by-step fixes.
Cannot optimize for 'index' on table 'orders' because the index is too wide and
This error occurs when the SQL query optimizer is unable to optimize a query because the index on the specified table is…
near ";" at character 12: unexpected token: ";". Expected "AS".
This error occurs when SQL parser encounters a syntax that it does not expect, in this case, an unexpected semicolon (";…
SQL syntax error: Unexpected keyword GROUP BY near 'date' in statement at or aro
This error occurs when the SQL syntax is incorrect, and the parser is unable to understand the query.…
SQLSTATE[HY000][2002] Can't connect to local MySQL server through socket '/var/r
This error occurs when the SQL client is unable to connect to the MySQL server. It typically happens when the MySQL serv…
SQLSTATE[HY000] [2002] Connection to MySQL server at 'localhost:3306' failed: un
This error occurs when the MySQL connection fails due to a certificate verification issue. It usually happens when the s…
SQL syntax error: expected ';', got ',' at line 3
This error occurs when SQL parser encounters an unexpected character or token while parsing the SQL query. In this case,…
Error converting data type nvarchar to datetime. Caught at SQL Server procedure
This error occurs when SQL Server encounters a datetime value that cannot be converted from a string to a datetime forma…
Missing comma between the 'SELECT' and 'FROM' clauses in the SQL query
This error occurs when the SQL query is missing a comma between two clauses, causing the database to interpret the query…
SQLSTATE[22023]: Clock specification error: 1264 Out of range value for column '
This error occurs when you attempt to insert a value into a numeric column that exceeds the defined range of acceptable …
SQLSTATE[HY000][1043] Unknown database 'my_database'
This error occurs when the database connection is established successfully, but the database specified in the connection…
SQL Error (1222): The following SQL statement failed to execute: 'ALTER TABLE or
This error occurs when a SQL statement is executed that attempts to modify a table that does not exist, or a column that…
Invalid use of index with the IN operator when using a derived table and window
This error occurs when a SQL query attempts to use an index with the IN operator on a derived table that also uses a win…
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