DAYOFFER

DAYOFFER sets out the participants’ daily components of participant bid containing details applying for the whole day (such as prices, daily energy constraint and fast start profiles). To retrieve full bid details, read in conjunction with PEROFFER.

Deprecation Warning

This table is in the HISTORICAL TABLES package, so is likely deprecated.

DAYOFFER data is confidential to the submitting participant until made public after 4am the next day.

The table DAYOFFER_D is quite distinct, with same field names (see DAYOFFER_D).

Column Schema

DUID

Dispatchable unit identifier

Warning

This column may contain funny characters such as / (slash) or # (hash). This may break hive-style partitioning.

For more information, see the dedicated documentation page.

SQL Type: VARCHAR2(10) Polars Type: pl.Categorical

This column is mandatory, and a primary key.

Example: W/HOE#2

OFFERDATE

Offer date of data

Warning

Despite what the name suggests, this is a datetime, not a date.

SQL Type: DATE Polars Type: pl.Datetime()

This column is mandatory, and a primary key.

Example: 2026/01/20 00:05:00

SETTLEMENTDATE

Market date starting at 04:00am

Warning

Despite what the name suggests, this is a datetime, not a date.

SQL Type: DATE Polars Type: pl.Datetime()

This column is mandatory, and a primary key.

Example: 2026/01/20 00:05:00

VERSIONNO

Version no. for given offer date

SQL Type: NUMBER(3,0) Polars Type: pl.UInt16

This column is mandatory, and a primary key.

DAILYENERGYCONSTRAINT

Maximum energy available from Energy Constrained Plant.

SQL Type: NUMBER(12,6) Polars Type: pl.Float64

This column is not mandatory.

ENTRYTYPE

Daily or Rebid

SQL Type: VARCHAR2(20) Polars Type: pl.Categorical

This column is not mandatory.

LASTCHANGED

Last date and time record changed

For more information, see the dedicated documentation page.

SQL Type: DATE Polars Type: pl.Datetime()

This column is not mandatory.

Example: 2026/01/20 00:05:00

MINIMUMLOAD

Minimum MW load fast start plant in MW

SQL Type: NUMBER(6,0) Polars Type: pl.Int32

This column is not mandatory.

MR_FACTOR

Mandatory Restriction Price Scaling Factor

SQL Type: NUMBER(16,6) Polars Type: pl.Float64

This column is not mandatory.

NORMALSTATUS

ON/OFF for loads

SQL Type: VARCHAR2(3) Polars Type: pl.Boolean

This column is not mandatory.

AEMO's documentation says this is a string type, even though it is logically a binary value. You may want to map letters to a boolean with {'ON': 1, 'OFF': 0}.

PRICEBAND1

Price for Availability Band 1

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is not mandatory.

PRICEBAND2

Price for Availability Band 2

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is not mandatory.

PRICEBAND3

Price for Availability Band 3

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is not mandatory.

PRICEBAND4

Price for Availability Band 4

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is not mandatory.

PRICEBAND5

Price for Availability Band 5

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is not mandatory.

PRICEBAND6

Price for Availability Band 6

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is not mandatory.

PRICEBAND7

Price for Availability Band 7

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is not mandatory.

PRICEBAND8

Price for Availability Band 8

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is not mandatory.

PRICEBAND9

Price for Availability Band 9

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is not mandatory.

PRICEBAND10

Price for Availability Band 10

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is not mandatory.

REBIDEXPLANATION

Explanation for all rebids and inflexibilities

SQL Type: VARCHAR2(64) Polars Type: str

This column is not mandatory.

T1

Time to synchronise in minutes

SQL Type: NUMBER(6,0) Polars Type: pl.Int32

This column is not mandatory.

T2

Time to minimum load in minutes

SQL Type: NUMBER(6,0) Polars Type: pl.Int32

This column is not mandatory.

T3

Time at minimum load in minutes

SQL Type: NUMBER(6,0) Polars Type: pl.Int32

This column is not mandatory.

T4

Time to shutdown in minutes

SQL Type: NUMBER(6,0) Polars Type: pl.Int32

This column is not mandatory.

BANDQUANTISATIONID

Not used

SQL Type: NUMBER(2,0) Polars Type: pl.Int8

This column is unused.

CONTINGENCYPRICE

Not used

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is unused.

MAXRAMPDOWN

Not used

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is unused.

MAXRAMPUP

Not used

SQL Type: NUMBER(9,2) Polars Type: pl.Float64

This column is unused.

SELFCOMMITFLAG

Not used

SQL Type: VARCHAR2(1) Polars Type: pl.Categorical

This column is unused.

New Data Timing

Daily

Code Examples

Polars

Casting is enums, categoricals etc is not essential, but may speed up parsing. Swapping int for pl.UInt16, pl.Int32 would also speed up parsing. However some of the datatypes are inferred, so they may be wrong.

This code deduplicates for you. Deduplication is normally only required across multiple months.

This code assumes that all columns are present, which may not be true for older files.

import polars as pl
import polars.selectors as cs

# e.g. "2029/03/15 00:05:00"
dt_s_fmt = "%Y/%m/%d %H:%M:%S"

csv_paths = ["SOMEFILE.CSV", "OTHERFILE.CSV"]

lf = (
    pl.concat(
        [
            pl.scan_csv(
                csv_path,  # must be unzipped beforehand
                skip_rows=1,  # skip the header
                infer_schema=False,  # much faster
            )
            .filter(cs.by_index(0) == "D")  # drop the footer
            .select(~cs.by_index(range(4)))  # drop metadata columns
            for csv_path in csv_paths
        ],
        how="diagonal_relaxed",
    )
    .with_columns(pl.col("NORMALSTATUS").replace({"ON": 1, "OFF": 0}))
    .with_columns(
        pl.col("OFFERDATE", "SETTLEMENTDATE", "LASTCHANGED").str.strptime(
            pl.Datetime, dt_s_fmt
        ),
    )
    # Polars can't cast string straight to bool. Need to go via something else.
    .cast({"NORMALSTATUS": pl.UInt8})
    .cast(
        {
            "DUID": pl.Categorical,
            "VERSIONNO": int,  # or pl.UInt16
            "DAILYENERGYCONSTRAINT": pl.Float64,
            "ENTRYTYPE": pl.Categorical,
            "MINIMUMLOAD": int,  # or pl.Int32
            "MR_FACTOR": pl.Float64,
            "NORMALSTATUS": pl.Boolean,
            "PRICEBAND1": pl.Float64,
            "PRICEBAND2": pl.Float64,
            "PRICEBAND3": pl.Float64,
            "PRICEBAND4": pl.Float64,
            "PRICEBAND5": pl.Float64,
            "PRICEBAND6": pl.Float64,
            "PRICEBAND7": pl.Float64,
            "PRICEBAND8": pl.Float64,
            "PRICEBAND9": pl.Float64,
            "PRICEBAND10": pl.Float64,
            "REBIDEXPLANATION": str,
            "T1": int,  # or pl.Int32
            "T2": int,  # or pl.Int32
            "T3": int,  # or pl.Int32
            "T4": int,  # or pl.Int32
            "BANDQUANTISATIONID": int,  # or pl.Int8
            "CONTINGENCYPRICE": pl.Float64,
            "MAXRAMPDOWN": pl.Float64,
            "MAXRAMPUP": pl.Float64,
            "SELFCOMMITFLAG": pl.Categorical,
        }
    )
    # Drop deprecated/unused columns
    .drop(
        "BANDQUANTISATIONID",
        "CONTINGENCYPRICE",
        "MAXRAMPDOWN",
        "MAXRAMPUP",
        "SELFCOMMITFLAG",
    )
    # Deduplicate
    # We want one row per ['DUID', 'OFFERDATE', 'SETTLEMENTDATE', 'VERSIONNO']
    # Tie-breaker: greatest value of ['LASTCHANGED']
    .sort(["LASTCHANGED"], descending=False)
    .unique(subset=["DUID", "OFFERDATE", "SETTLEMENTDATE", "VERSIONNO"], keep="last")
)

Nemosis

This table is not yet available in Nemosis.

Availability

AEMO's documentation states that this table's visibility is "Private & Public Next-Day". However, it is not available in the public monthly MMSDM archive. AEMO probably call this public because it is available to all market participants over private FTP.

There is a chance that is is still public to non-participants. It may only be available for some months; or (rarely) it may be available in a non-standard location.

Deduplication and PDR Loader Configuration

The primary keys are:

DUID
OFFERDATE
SETTLEMENTDATE
VERSIONNO

PDR Loader configuration does not mention this table, so it is unclear how to choose which row to keep when there are multiple rows for a given set of primary keys.

You should probably take the row with the maximum LASTCHANGED.