FLIP
The FLIP command flips the byte ordering on the specified item opposite
its current ordering. For example, if a table is currently stored in LITTLE
ENDIAN format, FLIP will change the byte ordering to BIG ENDIAN. This
can become necessary for example, when a binary file is copied from one
operating system to another.
FLIP is not the same as the SET ENDIAN command which only affects the
data as it is returned to OdxSQL. FLIP actually affects the data in the
file.
The FLIP command can be used on a file, a table in a database, or all
the tables in a database.
Syntax
FLIP <DATABASE | TABLE | FILE> name [ON [INSTANCE] instance]
[WITH options]
FLIP
Required.
DATABASE | TABLE | FILE name
Required. Flip the bytes on an entire database, a single table in a database,
or a file. name is the name of the database, table, or file.
DATABASE - Change the byte ordering on every table in the database by
using the FLIP DATABASE command. OdxSQL will scan every table to determine
which columns need to be flipped, calculate the offsets and perform the
flip.
TABLE - Change the byte ordering on any table in the environment catalog.
It will scan the table to determine which columns need to be flipped,
calculate the necessary offsets and perform the flip.
FILE - Change the byte ordering on a single file. When using this command
on a file, OdxSQL will prompt the user for the offsets and lengths of
the data in the file.
ON INSTANCE instancenumber
Optional. Specify the instance on which to perform the flip. instancenumber
is the integer instance number created when the connection to the Environment
file was opened. If omitted, the current instance contained in the instance
element of the Status array will be used. The INSTANCE keyword is optional.
The ON keyword is required if the instance is specified.
WITH options
Optional. A comma separated list of options to apply to this command.
Options
Example
DATABASE | FILE | TABLE
DATABASE
The following example flips the entire Orders sample flat file database.
>connect orders.env
> flip database orders
Flipping 6 tables in database ORDERS
[1 of 6] CUSTOMERS - 999 rows required flipping.
[2 of 6] PRODUCTS - 99 rows required flipping.
[3 of 6] ACTIVITY - 6540 rows required flipping.
[4 of 6] CUST_NOTES - 259 rows required flipping.
[5 of 6] ORDERS - 10208 rows required flipping.
[6 of 6] INVENTORY - 204 rows required flipping.
All tables flipped
>
FILE
> export customer_no, company, licensee from customers
where state='co' to colo.txt with delete
38 rows exported to colo.txt
> flip file colo.txt
Flipping file: C:\omnidex\colo.txt
OdxSQL prompts for the record length. This is 48, CUSTOMER_NO is a 4
byte integer, COMPANY is a 40 byte character string, and LICENSEE is a
4 byte integer.
Record length: 48
colo.txt is 1.8K and has 38 rows
OdxSQL the prompts for the Offset and length of the fields to be flipped.
These are only the binary fields, therefore the length value specified
can only be 2, 4 and 8. The offset must be determined, accounting for
the space taken by the non-binary fields, as shown:
1) Offset: 0
1) Length: 4
2) Offset: 44
2) Length: 4
3) Offset:
38 rows flipped in colo.txt
>
An easier way to accomplish the same results would be to create an Omnidex
Environment Catalog containing the table definition for the file, then
use the FLIP TABLE command (see below).
TABLE
The following environment catalog entry defines the file used in the
example above.
TABLE "COLO"
PHYSICAL "C:\omnidex\demodata\colo.txt"
PARENT KEY "CUSTOMER_NO"
COLUMN "CUSTOMER_NO" DATATYPE INTEGER LENGTH 4
COLUMN "COMPANY" DATATYPE CHAR LENGTH 40
COLUMN "LICENSEE" DATATYPE INTEGER LENGTH 4
Connect to the environment catalog containing this entry and run the
FLIP TABLE command.
> flip table colo
38 COLO rows required flipping.
>
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