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https://dev.mysql.com/doc/connector-net/en/connector-net-faq.html
To stop that, once all your commands have been added you need to disconnect the CommandBuilder from the DataAdapter: cb.DataAdapter = null; The last requirement is to make sure the id that is returned by last_insert_id() has the correct name.
https://dev.mysql.com/doc/connector-net/en/connector-net-programming-blob-writing.html
To write a file to a database, we need to convert the file to a byte array, then use the byte array as a parameter to an INSERT query. After assigning the byte array as a parameter of the MySqlCommand object, the ExecuteNonQuery method is called ...
https://dev.mysql.com/doc/connector-net/en/connector-net-programming-datetime-invalid.html
The MySqlDateTime class supports NULL dates, while the .NET DateTime class does not. This can cause errors when trying to convert a MySQLDateTime to a DateTime if you do not check for NULL first. Although it is strongly recommended that you avoid ...
https://dev.mysql.com/doc/connector-net/en/connector-net-programming-prepared.html
Prepared statements can provide significant performance improvements on queries that are executed more than one time. Prepared execution is faster than direct execution for statements executed more than once, primarily because the query is parsed ...
https://dev.mysql.com/doc/connector-python/en/connector-python-api-errors-dataerror.html
Examples are a column set to NULL that cannot be NULL, out-of-range values for a column, division by zero, column count does not match value count, and so on. This exception is raised when there were problems with the data.
https://dev.mysql.com/doc/internals/en/better-protocols-example.html
SET @aux = 1; SELECT @aux AS "content of @aux is"; content of @aux is 1 SELECT @aux AS "content of @aux is"; content of @aux is NULL . The output becomes less clear because there is no indication that the connection has been changed.
https://dev.mysql.com/doc/internals/en/defining-filename-extensions.html
Extensions are expected in the form of a null-terminated string array. Storage engines are required to provide the MySQL server with a list of extensions used by the storage engine with regard to a given table, its data and indexes.
https://dev.mysql.com/doc/internals/en/optimizer-constants-constant-tables.html
unique_not_null_column INT NOT NULL UNIQUE then this expression FROM Table1 ... Here's an example: SELECT Table1.unique_not_null_column, Table2.any_column FROM Table1, Table2 WHERE Table1.unique_not_null_column = Table2.any_column AND ... A MySQL ...
https://dev.mysql.com/doc/internals/en/optimizer-determining-join-type.html
When evaluating a conditional expression, MySQL decides what join type the expression has. (Again: despite the word “join”, this applies for all conditional expressions, not just join expressions. index: a sequential scan on an index ALL: a ...
https://dev.mysql.com/doc/internals/en/optimizer-group-by-related-conditions.html
Note that the query SELECT COUNT(column1) FROM Table1; is not subject to the same optimization, unless column1 is defined as NOT NULL. (You can, however, rely on that rule with GROUP BY, unless the query includes ORDER BY NULL.) See: ... These are ...