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https://dev.mysql.com/doc/connector-python/en/connector-python-api-mysqlcursordict.html
Example: cnx = mysql.connector.connect(database='world') cursor = cnx.cursor(dictionary=True) cursor.execute("SELECT * FROM country WHERE Continent = 'Europe'") print("Countries in Europe:") for row in cursor: print("* ...The keys for each ...
https://dev.mysql.com/doc/connector-python/en/connector-python-api-mysqlcursorprepared.html
Example: cursor = cnx.cursor(prepared=True) stmt = "SELECT fullname FROM employees WHERE id = %s" # (1) cursor.execute(stmt, (5,)) # (2) # ... In MySQL, there are two ways to execute a prepared statement: Use the PREPARE and EXECUTE statements. To ...
https://dev.mysql.com/doc/connector-python/en/connector-python-coding.html
You use SELECT statements to query only the precise items you need, and aggregate functions to perform calculations across multiple items. See Data Manipulation Statements, Data Definition Statements, and SELECT Statement for the main classes of ...
https://dev.mysql.com/doc/internals/en/a-mysql-client-logs-in.html
00 00 27 75 3e 6f 38 66 79 4e 00 ff f7 08 02 00 ..'u>o8fyN...... 00 00 00 00 00 00 00 00 00 00 00 00 00 57 4d 5d .............WM] 6a 7c 53 68 32 5c 59 2e 73 00 j|Sh2\Y.s. which responds with a handshake packet which contains the version, some flags ...
https://dev.mysql.com/doc/internals/en/avoid-too-dense-code.html
Unfortunate example: select 1+1,1-1,1+1*2,8/5,8%5,mod(8,5),mod(8,5)|0,-(1+1)*-2; Improved example: SELECT 1 + 1, 1 - 1, 1 + 1 * 2, 8 / 5, 8 % 5, MOD(8,5), MOD(8,5) | 0, -(1+1) * -2; . except you intend to check the parser or the performance of the ...
https://dev.mysql.com/doc/internals/en/caching.html
(This is a very quick in-memory table with hash index.) Join Buffer Cache For every “full join” in a SELECT statement the rows found are cached in a join cache. (A “full join” here means there were no keys that could be used to find rows for ...(Note that the some of the filenames contain an incorrect spelling of the word “cache.”) Key Cache A shared cache for all B-tree index blocks in the different NISAM ...
https://dev.mysql.com/doc/internals/en/character-set.html
For example: mysql> SELECT CHARACTER_SET_NAME, COLLATION_NAME FROM INFORMATION_SCHEMA.COLLATIONS WHERE ID = 255; +--------------------+--------------------+ | CHARACTER_SET_NAME | COLLATION_NAME | +--------------------+--------------------+ | ...
https://dev.mysql.com/doc/internals/en/dbug-sleep.html
let $wait_condition= SELECT 1 FROM INFORMATION_SCHEMA.PROCESSLIST WHERE ID = $conn1_id AND STATE = 'DBUG sleep'; # Run the condition in a loop until it becomes true. In cases where the normal server code does not have a block point at the critical ...
https://dev.mysql.com/doc/internals/en/error-flags.html
(This allows one to catch all error messages generated by a statement) thd->lex->current_select->no_error This is set to in case likes INSERT IGNORE ... In this case we ignore all not fatal errors generated by the select. The following flags can be ...
https://dev.mysql.com/doc/internals/en/error-messages-storage-engine.html
For example: Got error 788 'Could not connect to remote server fed.bb.pl' from FEDERATED The Got error %d part will be returned in the user's selected language, but the handler-specific one will use English (unless the handler supports returning the ... To add error messages for table handlers, the following example may be ...