SYSEXTCOLS
The sysextcols system catalog table contains a row that describes each of the internal columns in external table tabid of format type (fmttype) FIXED.
The sysextcols table has the following columns.
| Column | Type | Explanation |
|---|---|---|
| tabid | INTEGER | Unique identifying code of a table |
| colno | SMALLINT | Code identifying the column |
| exttype | SMALLINT | Code identifying an external column type |
| extstart | SMALLINT | Starting position of column in the external data file |
| extlength | SMALLINT | External column length (in bytes) |
| nullstr | CHAR(256) | Represents NULL in external data |
| decprec | SMALLINT | Precision for external decimals |
| extstype | VARCHAR(128,0) | External type name |
No entries are stored in sysextcols for DELIMITED or HCL OneDB™ format external files.
You can use the DBSCHEMA utility to write out the description of the external tables. To query these system catalog tables about an external table, use the tabid as stored in systables with tabtype = ‘E'.
An index on the tabid column allows duplicate values.