GetColumns returns an Array in which each row contains one column from the database connected to using connection.  A column in the Array is data associated with the column.  The output option controls the columns and their order in the returned Array.

The opts argument can contain one or more of the following equations.

output = list containing one or more of the literal symbols: name, catalog, schema, table, and type

The output option specifies the columns of information to return and their order. By default, only the name is returned. Some databases do not support all these fields.

- name returns the name of the column.

- catalog returns the name of the catalog that contains the table.

- schema returns the name of the schema used in the table.

- table returns the name of the table that contains the column.

- type returns the SQL type of the column.

catalog = string

Return only columns from the specified catalog. To return columns from tables not in a catalog, specify the empty string ("").  By default, no restrictions are applied.

schema = string

Return only columns from databases in which the schema matches the specified pattern. The pattern can consist of any valid schema name characters and the special characters % and _. A % matches any string and an _ matches any character. To match a literal _ or %, you must prepend the escape character \.  For example, to match a _, use \_. To return columns from databases that do not use a schema, specify the empty string ("").  By default, no restrictions are applied.

table = string

Return only columns for which the table matches the specified pattern. The pattern can consist of any valid table name characters and the special characters % and _. A % matches any string and an _ matches any character. To match a literal _ or %, you must prepend the escape character \.  For example, to match a _, use \_. By default, no restrictions are applied.

column = string

Return only columns for which the name matches the specified pattern. The pattern can consist of any valid table name characters and the special characters % and _. A % matches any string and an _ matches any character. To match a literal _ or %, you must prepend the escape character \.  For example, to match a _, use \_. By default, no restrictions are applied.

$\mathrm{driver}≔\mathrm{Database}\left[\mathrm{LoadDriver}\right]\left(\right)\:$

$\mathrm{conn}≔\mathrm{driver}:-\mathrm{OpenConnection}\left(\mathrm{url}\,\mathrm{name}\,\mathrm{pass}\right)\:$

$\mathrm{conn}:-\mathrm{GetColumns}\left('\mathrm{output}'=\left['\mathrm{table}'\,'\mathrm{name}'\right]\right)$

$\left[\begin{array}{cc}''Table1''& ''size''\\ ''Table1''& ''number''\\ ''Table2''& ''mass''\\ ''Table2''& ''density''\\ ''Table3''& ''distance''\end{array}\right]$

$\mathrm{conn}:-\mathrm{GetColumns}\left('\mathrm{table}'=''Table1''\,'\mathrm{output}'=\left['\mathrm{name}'\right]\right)$

$\left[\begin{array}{c}''size''\\ ''number''\end{array}\right]$

$\mathrm{conn}:-\mathrm{GetColumns}\left('\mathrm{column}'=''\%a\%''\,'\mathrm{output}'=\left['\mathrm{name}'\,'\mathrm{table}'\,'\mathrm{type}'\right]\right)$

$\left[\begin{array}{ccc}''mass''& ''Table1''& ''DOUBLE''\\ ''distance''& ''Table3''& ''DOUBLE''\end{array}\right]$