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The LOAD_DATABASE command allows the user to load data into a selected database from a specified source file. The data format used in such files - MTDATA database loading files - is specified in Appendix 1. The database to be augmented must be on the list of those active during the current MTDATA session. If it is password protected then the correct password must be supplied before any additions or alterations can be made. The user is able to decide whether or not to overwrite any datasets encountered in the database which are duplicated in the loading file. This decision can be made either interactively as and when problems occur or by issuing a global command at the start of the loading procedure.








database = (the last database referred to in a UTILITY command)

password = <""> 

query = (the user is prompted for a decision when problems occur)

format = MTDATA


load_data data=newdata file="newdata.loa" ! 

lo_da fi="gooddata.loa" !

lo_data fil="project6.loa" password "bdjd32" q=i !

lo_dat data=olddata fil="update.loa" query=over !

loa_data fil="UPPER" format=UPPERCASE_MTDATA !

Parameter values:

DATABASE takes the value <"database name">

The DATABASE parameter is used to specify the name of the database into which data are to be loaded. Note that the database name should NOT be entered in quotes and must appear on the current active list (see STATISTICS command). If the LOAD_DATA command is used without specifying a DATABASE name, an attempt will be made to load data into the last database referred to in a successfully executed UTILITY command.

PASSWORD takes the value <"database password">

The correct database password must be given, in quotes, following the PASSWORD parameter in order to load any data into a password protected database. There is of course no need to use the PASSWORD parameter for databases which have no password protection.

FILE  takes the value <"data loading file name">

The FILE parameter is used to specify the name of the source file from which data are to be loaded into the chosen database. The file name should be entered in quotes. For information on the structure of MTDATA data loading files see Appendix 1. Note that a data loading file (source file) name MUST be supplied before any data can be loaded into a database.


The QUERY parameter allows the user to specify what action should be taken if, during the data loading process, data are found in the data loading file for a unary or interaction already present in the selected database. The new data can either be APPENDed to the database (with a new phase name or isomer label), IGNOREd or the old data OVERWRITten. If no course of action is established via the QUERY parameter the user will be prompted for a new decision each time duplicate datasets are encountered during the loading process. This can be tedious especially when making a minor update to a very large database.

APPEND  On encountering two sets of data for the same unary or interaction that from the loading file will be appended to the database under a new phase name or isomer label. The user will be prompted for this new phase name or isomer label.

IGNORE  On encountering two sets of data for the same unary or interaction that from the loading file will be ignored. The database will remain unchanged.

OVERWRITE  On encountering two sets of data for the same unary or interaction that from the loading file will be used to overwrite that already in the database.


The FORMAT parameter is used to identify the data format used in the source file from which data are to be loaded into the chosen database. For most practical purposes this will be the MTDATA data loading file format described in Appendix 1. A minor variation of this format is sometimes encountered in which the chemical symbols of the elements are written in upper case. CO, for example, would then be interpreted as cobalt and not as carbon monoxide (which would be C1O1). Selecting a FORMAT of UPPERCASE_MTDATA allows this convention to be taken into account.

MTDATA The MTDATA format is that described in Appendix 1. Normal chemical symbols containing both upper and lower case letters must be used.

UPPERCASE_MTDATA   The UPPERCASE_MTDATA format is identical to the MTDATA format except that chemical symbols are expected to be in upper case only (eg CO for cobalt). Compounds such as carbon monoxide are represented by entering the stoichiometry number "1" explicitly where appropriate or by using an underscore character (or blank) to separate different elements (eg C1O1 or C_O).

General comments:

A summary of the total number of species, phases and interactions listed is given at the end of each database listing. This is correct way of finding out how much data a database holds. The figures given in response to the STATISTICS command are not meant to represent the total number of data items in a database but rather the total number of data loading events (see STATISTICS).

There are three main types of error which may be encountered in loading data into an MTDATA database:

(a) A mistake in the format of the data loading file.

If an entry is found in a data loading file which is inconsistent with the data formats described in Appendix 1, an error message is issued (to the screen) as follows:


All error messages of this type are also written to a text file named mtload.err. Such errors are usually the result of a simple typing mistake or the omission of a number at some point.

(b) Interacting species are not in alphabetical order in the data loading file.

Data are not retrieved during database searches for interactions where the interacting species are not specified in alphabetical order. Care must therefore be taken to ensure that interacting species are always given in alphabetical order in data loading files as this order is preserved on loading data into a database. Since no check on the order of interacting species is made during the data loading process no error messages appear for this type of error.

(c) The correct password is not supplied for a password protected database.

In order to be able to load data into a password protected database the correct password must be supplied. If an incorrect password or no password at all is given then the following error message is issued:




Updated 23 June 2010