Add support for all flags from mysql in the PDO MySql driver in the getColumnMeta function.

[deAtog]

Description

The getColumnMeta function currently returns a small subset of the flags from the native mysql library as shown here:

php-src/ext/pdo_mysql/mysql_statement.c

Lines 790 to 801 in 6727f54

	if (IS_NOT_NULL(F->flags)) {
	add_next_index_string(&flags, "not_null");
	}
	if (IS_PRI_KEY(F->flags)) {
	add_next_index_string(&flags, "primary_key");
	}
	if (F->flags & MULTIPLE_KEY_FLAG) {
	add_next_index_string(&flags, "multiple_key");
	}
	if (F->flags & UNIQUE_KEY_FLAG) {
	add_next_index_string(&flags, "unique_key");
	}

Please add support for all applicable flags specified here:

php-src/ext/mysqlnd/mysqlnd_enum_n_def.h

Lines 337 to 353 in 6727f54

	#define NOT_NULL_FLAG 1
	#define PRI_KEY_FLAG 2
	#define UNIQUE_KEY_FLAG 4
	#define MULTIPLE_KEY_FLAG 8
	#define BLOB_FLAG 16
	#define UNSIGNED_FLAG 32
	#define ZEROFILL_FLAG 64
	#define BINARY_FLAG 128
	#define ENUM_FLAG 256
	#define AUTO_INCREMENT_FLAG 512
	#define TIMESTAMP_FLAG 1024
	#define SET_FLAG 2048
	#define NO_DEFAULT_VALUE_FLAG 4096
	#define ON_UPDATE_NOW_FLAG 8192
	#define PART_KEY_FLAG 16384
	#define GROUP_FLAG 32768
	#define NUM_FLAG 32768

These flags provide valuable information about the column returned and how to potentially process it. For instance, one might need to treat binary strings different from non-binary strings. Without the binary flag, it is impossible to know whether or not a string might require special handling without examining the values of the result set. Additionally, consider adding a native_flags attribute which returns the unmodified numeric value of the flags from the mysql library.