CDA ci860 Specifications download pdf (Page 472)

100

101

Accessing 800xA via OLE DB

472 3BDS011222-510 B

• You cannot use the keywords COUNT and RESAMPLE without using the

Aggregate keyword.

All the keywords must be written in capital letters. If you do not write the command

line according to the syntax and restriction above the provider will return an error

code that tells you that you have an invalid argument.

When you use GUIDs to identify the object you also need to use it for the aspect and

vice verse.

The Time Definition

When you use the keywords TO and FROM you have to give the time in so called

OPCHDA_TIME. It is a time that is considered to be a relative time local to the

server. The format for the relative time is:

• keyword +/-offset +/-offset …

Where keyword and offset are as specified in Table 27 and Table 28 below. White

space is ignored. Each offset must be preceded by a signed integer that specifies the

number and direction of the offset. If the integer preceding the offset is unsigned,

the value of the preceding sign is assumed (beginning default sign is positive).

The keyword refers to the beginning of the specified time period. DAY means the

timestamp at the beginning of the current day (00:00 hours, midnight), MONTH

means the timestamp at the beginning of the current month, and so on.

For example if you write, “DAY -1D+7H30M”, then it represent the start time for

data request for a daily report beginning at 7:30 in the morning of the current day

(DAY = the first timestamp for today, -1D makes it the first timestamp for yesterday,

+7H takes it to 7 a.m. yesterday, +30M to 7:30 a.m. yesterday (note that the + on the

last term is carried over from the last term).

See the OPC Historical Data Access Custom Interface Specification 1.0

1 2 ... 467 468 469 470 471 472 473 474 475 476 477 ... 603 604

Comments to this Manuals

No comments

CDA ci860 Specifications Page 472

Comments to this Manuals