validateLimits: Validate the limits imposed on a column
In talithafs/dzVis-Package: Data Visualization with Data Zoom

Description Usage Arguments Value Validation rules

Checks the validity of inequality restrictions imposed on a column. It uses a direct connection to the dzVis database or a data.frame as the data source.

1	validateLimits(data, columnName, min, max)

`data`	A `data.frame` with the actual data source or a `character` containing the name of the table in the dzVis database. If it is a `data.frame`, a connection to the dzVis database WILL NOT be estabilished. If it is a `character`, a connection WILL be estabilished.
`columnName`	A `character`. The name of the column to be checked.
`min`	A `numeric` value, a `character` or a `Date` in the format 'yyyy-mm-dd'. Lower bound for the column value. Should be set to `NULL` when not applicable.
`max`	A `numeric` value, a `character` or a `Date` in the format 'yyyy-mm-dd'. Upper bound for the column value. Should be set to `NULL` when not applicable.

A character. The constant .VALID if the limits are valid and an error message, otherwise.

min and max must be of the same type: both numeric or both character.
min must be less than max
If min and max type is numeric, the column values must also be numeric in R and int or double in the database.
If min and max type is character, the column values must be character in R and varchar in the database.
If min and max type is Date, the column values must be Date in R and date or datetime in the database.