(PECL ibm_db2 >= 1.0.0)
db2_columns — Returns a result set listing the columns and associated metadata for a table
$connection
   [, string $qualifier
   [, string $schema
   [, string $table-name
   [, string $column-name
  ]]]] )Returns a result set listing the columns and associated metadata for a table.
connectionA valid connection to an IBM DB2, Cloudscape, or Apache Derby database.
qualifier
       A qualifier for DB2 databases running on OS/390 or z/OS servers. For
       other databases, pass NULL or an empty string.
      
schemaThe schema which contains the tables. To match all schemas, pass '%'.
table-name
       The name of the table or view. To match all tables in the database,
       pass NULL or an empty string.
      
column-name
       The name of the column. To match all columns in the table, pass NULL
       or an empty string.
      
Returns a statement resource with a result set containing rows describing the columns matching the specified parameters. The rows are composed of the following columns:
| Column name | Description | 
|---|---|
| TABLE_CAT | Name of the catalog. The value is NULL if this table does not have catalogs. | 
| TABLE_SCHEM | Name of the schema. | 
| TABLE_NAME | Name of the table or view. | 
| COLUMN_NAME | Name of the column. | 
| DATA_TYPE | The SQL data type for the column represented as an integer value. | 
| TYPE_NAME | A string representing the data type for the column. | 
| COLUMN_SIZE | An integer value representing the size of the column. | 
| BUFFER_LENGTH | Maximum number of bytes necessary to store data from this column. | 
| DECIMAL_DIGITS | The scale of the column, or NULLwhere scale is not applicable. | 
| NUM_PREC_RADIX | An integer value of either 10 (representing
         an exact numeric data type), 2 (representing an
         approximate numeric data type), or NULL(representing a data type for
         which radix is not applicable). | 
| NULLABLE | An integer value representing whether the column is nullable or not. | 
| REMARKS | Description of the column. | 
| COLUMN_DEF | Default value for the column. | 
| SQL_DATA_TYPE | An integer value representing the size of the column. | 
| SQL_DATETIME_SUB | Returns an integer value representing a datetime subtype code,
         or NULLfor SQL data types to which this does not apply. | 
| CHAR_OCTET_LENGTH | Maximum length in octets for a character data type column, which
         matches COLUMN_SIZE for single-byte character set data, or NULLfor
         non-character data types. | 
| ORDINAL_POSITION | The 1-indexed position of the column in the table. | 
| IS_NULLABLE | A string value where 'YES' means that the column is nullable and 'NO' means that the column is not nullable. |