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https://dev.mysql.com/mysql-fetch-lengths.html
In addition, if the result set contains binary data, you must use this function to determine the size of the data, because strlen() returns incorrect results for any field containing null characters. The length for empty columns and for columns ...
https://dev.mysql.com/mysql-hex-string.html
The result is placed in the to argument, followed by a terminating null byte. When mysql_hex_string() returns, the contents of to is a null-terminated string. The return value is the length of the encoded string, not including the terminating null ... unsigned long mysql_hex_string(char *to, const char *from, unsigned long length) This function creates a legal SQL string for use in an SQL ...
https://dev.mysql.com/mysql-stmt-fetch.html
If a fetched data value is a NULL value, the *is_null value of the corresponding MYSQL_BIND structure contains TRUE (1). int mysql_stmt_fetch(MYSQL_STMT *stmt) mysql_stmt_fetch() returns the next row in the result set. It can be called only while ...
https://dev.mysql.com/mysql-store-result.html
mysql_store_result() returns NULL if the statement did not return a result set (for example, if it was an INSERT statement), or an error occurred and reading of the result set failed. (An empty result set differs from a null pointer as a return ...
https://dev.mysql.com/non-typed-operators.html
->> Return value from JSON column after evaluating path and unquoting the result; equivalent to JSON_UNQUOTE(JSON_EXTRACT()). / Division operator := Assign a value = Assign a value (as part of a SET statement, or as part of the SET clause in an ...
https://dev.mysql.com/obtaining-plugin-information.html
Any that have a PLUGIN_LIBRARY value of NULL are built in and cannot be unloaded. row *************************** PLUGIN_NAME: binlog PLUGIN_VERSION: 1.0 PLUGIN_STATUS: ACTIVE PLUGIN_TYPE: STORAGE ENGINE PLUGIN_TYPE_VERSION: 50158.0 PLUGIN_LIBRARY: ... There are several ways to determine which plugins are installed in the server: The INFORMATION_SCHEMA.PLUGINS table contains a row for each loaded ...
https://dev.mysql.com/other-vendor-data-types.html
To facilitate the use of code written for SQL implementations from other vendors, MySQL maps data types as shown in the following table. These mappings make it easier to import table definitions from other database systems into MySQL. If you create ...
https://dev.mysql.com/outer-join-optimization.html
If there is a row in A that matches the WHERE clause, but there is no row in B that matches the ON condition, an extra B row is generated with all columns set to NULL. For a LEFT JOIN, if the WHERE condition is always false for the generated NULL ...
https://dev.mysql.com/partitioning-key.html
Unlike the case with other partitioning types, columns used for partitioning by KEY are not restricted to integer or NULL values. Partitioning by key is similar to partitioning by hash, except that where hash partitioning employs a user-defined ...
https://dev.mysql.com/setup-threads-table.html
row *************************** NAME: thread/performance_schema/setup ENABLED: YES HISTORY: YES PROPERTIES: singleton VOLATILITY: 0 DOCUMENTATION: NULL ... row *************************** NAME: thread/sql/main ENABLED: YES HISTORY: YES PROPERTIES: ...It exposes thread class names and attributes: mysql> SELECT * FROM performance_schema.setup_threads\G *************************** ...
Document created the 26/06/2006, last modified the 26/10/2018
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