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(mysql.info)mysql_fetch_field

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`mysql_fetch_field()'
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`MYSQL_FIELD *mysql_fetch_field(MYSQL_RES *result)'

Description
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Returns the definition of one column of a result set as a `MYSQL_FIELD'
structure. Call this function repeatedly to retrieve information about
all columns in the result set.  `mysql_fetch_field()' returns `NULL'
when no more fields are left.

`mysql_fetch_field()' is reset to return information about the first
field each time you execute a new `SELECT' query.  The field returned by
`mysql_fetch_field()' is also affected by calls to `mysql_field_seek()'.

If you've called `mysql_query()' to perform a `SELECT' on a table but
have not called `mysql_store_result()', MySQL returns the default blob
length (8K bytes) if you call `mysql_fetch_field()' to ask for the
length of a `BLOB' field.  (The 8K size is chosen because MySQL doesn't
know the maximum length for the `BLOB'. This should be made
configurable sometime.) Once you've retrieved the result set,
`field->max_length' contains the length of the largest value for this
column in the specific query.

Return Values
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The `MYSQL_FIELD' structure for the current column. `NULL' if no
columns are left.

Errors
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None.

Example
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     MYSQL_FIELD *field;
     
     while((field = mysql_fetch_field(result)))
     {
         printf("field name %s\n", field->name);
     }