SQL and Database Diagnostic Tools

Use these browser-based helpers to narrow down common MySQL and PostgreSQL errors. The diagnostic helpers do not connect to a database or execute SQL; the SQLite playground runs SQLite locally in your browser. Read each tool’s limits before changing a schema or query.

Run SQLite SQL in your browser

Open the SQLite SQL playground to create tables, run queries, inspect result sets, or open a local SQLite file in a temporary in-memory database. SQL and data stay in your browser; the tool does not connect to a server.

Find a MySQL error guide

Filter MySQL error guides by code or message to narrow the troubleshooting index. The full list remains available when the filter is cleared.

Filter PostgreSQL error guides by SQLSTATE or message to narrow the troubleshooting index. The full list remains available when the filter is cleared.

Triage a PostgreSQL error

Open the PostgreSQL error triage helper to choose a common SQLSTATE and see a first diagnostic step. It runs locally and does not need SQL text or a database connection.

Triage a MySQL connection error

Open the MySQL connection and authentication triage helper to distinguish errors 1045, 1524, and 2059 from blocked-host, host-access, network, and database-privilege problems. It uses only error-code and connection-category choices in the browser.

Estimate MySQL connection pool capacity

Open the MySQL connection pool budget estimator to compare classic-protocol pool capacity with max_connections after other ordinary workloads. Enter values from the target server; the estimate runs locally in your browser.

Estimate a MySQL account connection limit

Open the MySQL account connection budget estimator to check whether pools sharing one user@host account exceed its effective max_user_connections limit. The estimate runs locally and does not send entered values.

Check a MySQL foreign-key definition

Open the MySQL foreign-key checker to compare integer and DECIMAL definitions, character sets and collations, table engines, and parent-table keys. It checks common requirements locally; it cannot prove that a foreign key will succeed.

Estimate PostgreSQL connection pool capacity

Open the PostgreSQL connection budget calculator to compare configured pool capacity against ordinary connection slots. Enter values from the target server; the calculation runs in your browser.

Compare a column name with your schema

• MySQL column-name checker: compare a column from Error 1054 with the names from the intended table and see close spelling suggestions.
• PostgreSQL column-name checker: compare a column from SQLSTATE 42703, including capitalization differences for quoted identifiers.

These checks and the SQLite playground run in your browser and do not connect to a database server. When Google Analytics is enabled, SQLiz records limited interaction metadata such as filter length and result count, checker outcome counts, calculator outcome categories, playground run outcome and result-set count, file import/export actions, or which directory link was clicked. It does not send entered filter text, SQL statements, schemas, connection settings, column names, file names, file sizes, database contents, or result values.