Check names for SQLite column name conventions and length limits.

Checks names for SQLite column name conventions and SPSS/Stata variable name limits, and applies appropriate variable name changes to GADSdat or all_GADSdat objects.

Usage

checkVarNames(
  GADSdat,
  checkKeywords = TRUE,
  checkDots = TRUE,
  checkDuplicates = TRUE,
  charLimits = NULL
)

Arguments

GADSdat: GADSdat or all_GADSdat object.
checkKeywords: Logical. Should SQLite keywords be checked and modified?
checkDots: Logical. Should occurrences of "." be checked and modified?
checkDuplicates: Logical. Should case insensitive duplicate variable names be checked and modified?
charLimits: Optional character vector of one or more program names(s) for the limit check (see details). Currently, these are implemented: c("SPSS", "Stata")

Value

Returns the original object with updated variable names.

Details

Invalid column names in a SQLite data base include

SQLite keywords (see sqlite_keywords),
column names with a "." in it and
duplicate variable names which arise from SQLite being case insensitive.

The corresponding variable name changes are

appending the suffix "Var" to all SQLite keywords,
changing all "." in variable names to "_", and
appending "_2" to case insensitive duplicated variable names.

Note that avoiding "." in variable names is beneficial for multiple reasons, such as avoiding confusion with S3 methods in R and issues when exporting to Stata.

Variable name length limits

The length of variable names is limited to 64 bytes in SPSS and to 32 characters in Stata. If more than one program name is provided in charLimits, the most restrictive among the chosen limits will be applied. Variable names exceeding that limit will be truncated and marked with the suffix "_tr".

Examples

# Change example data set (create an invalid variable name)
pisa2 <- changeVarNames(pisa, oldNames = "computer_age",
                        newNames = "computer.age")
#> computer.age has been renamed to computer_age

pisa3 <- checkVarNames(pisa2)