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====== Table Type ====== | ====== Table Type ====== | ||
- | A table is a collection of [[wp>Tuple|tuples]], where each tuple may be formed by several keys and values. The set of keys must be unique for each tuple. | + | A table is a collection of [[wp>Tuple|tuples]] organized in a special way, where each tuple may be formed by several keys and values. The set of keys in each row must be unique. |
[{{ :editors:table_basics_1.png?nolink |Table Basics}}] | [{{ :editors:table_basics_1.png?nolink |Table Basics}}] | ||
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[{{ :editors:table_basics_2.png?nolink |Table Basics}}] | [{{ :editors:table_basics_2.png?nolink |Table Basics}}] | ||
- | The set of all elements at the same position in all tuples defines a column. All columns must have a unique name. The names must follow the general name convention in Dinamica EGO, they must start with a "_" or a letter and must be formed by letters, numbers and underscores. Blanks in names are automatically replaced by "_" (underscore). | + | The set of all elements at the same position in all rows defines a column. All columns must have a unique name. The names must follow the general name convention in Dinamica EGO, they must start with a "_" or a letter and must be formed by letters, numbers and underscores. Blanks in names are automatically replaced by "_" (underscore). |
Keys and values can be represented using double precision [[wp>Floating_point|floating point numbers]], allowing the definition of integral and fractional values, or [[wp>String_(computer_science)|strings]]. | Keys and values can be represented using double precision [[wp>Floating_point|floating point numbers]], allowing the definition of integral and fractional values, or [[wp>String_(computer_science)|strings]]. | ||
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<note tip> | <note tip> | ||
- | The Dinamica documentation and error messages usually express a table format as a sequence of column names/types separated by commas. | + | The Dinamica documentation and error messages usually express a table format as a sequence of column names/types separated by commas. For example, the sequence “City_Id*#real, City_Population#real, City_Name#string” corresponds to a table with one key column and two value/data column. The key column is named “City_Id” with type Real Value Type and the data/value columns are named “City_Population” and “City_Name” with types Real Value Type and String Type, respectively. It is also possible to omit the column names and represent that table format as “*#real, #real, #string”. |
- | \\ | + | |
- | For example, the sequence “City_Id*#real, City_Population#real, City_Name#string” corresponds to a table with one key column and two value/data column. The key column is named “City_Id” with type Real Value Type and the data/value columns are named “City_Population” and “City_Name” with types Real Value Type and String Type, respectively. | + | |
- | \\ | + | |
- | It is also possible to omit the column names and represent the previous table format as “*#real, #real, #string”. | + | |
- | \\ | + | |
When stored as [[wp>Comma-separated_values]] files, tables may also use the column name/type syntax to represent the column attributes — the name, the indication whether it is key or data/value column, and its data type. | When stored as [[wp>Comma-separated_values]] files, tables may also use the column name/type syntax to represent the column attributes — the name, the indication whether it is key or data/value column, and its data type. | ||
</note> | </note> |