func:read

read(filterExpr, checked: true)

Read from database the first record which matches filter. If no matches found throw UnknownRecErr or null based on checked flag. If there are multiple matches it is indeterminate which one is returned. See readAll() for how filter works.

Examples:

read(site)                 // read any site rec
read(site and dis=="HQ")   // read site rec with specific dis tag
read(chiller)              // raise exception if no recs with chiller tag
read(chiller, false)       // return null if no recs with chiller tag