Jd/Ops create

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create col

  • string arg

createcol table col type
createcol /derived table col type verb
createcol /derived_mapped table col type verb

/derived creates a derived col
derived col is not mapped
derived col data is the result of verb derived_verb in custom.ijs
/derived_mapped creates a derived_mapped col
derived_mapped col is mapped
derived_mapped col data is the result of verb derived_mapped_verb in custom.ijs
  • boxed arg provides data to initialize the col

createcol table ; col ; type ; data

tutorials createcol , createcol_derived , createcol_derived_mapped



valid only after a dropdb
creates filefolder, initial files, and gets lock


  • deprecated - use createcol /derived


createtable [/a ...] table [coldefs]
createtable /pairs [/types] [/a ...] table ; pairs

/a min_rows multiplier extra_rows
when insert requires mapped col file resize, new size is:
default is 2000 1.5 0
/types - pairs have types in parens - cola(edate)

createtable with 0 or more cols

coldefs - col type [trailing-shape]
string arg coldefs separated by , or LF
boxed arg coldefs in separate boxes


createptable table pcol

allowed pcol types: int edate edatetime date datetime

table must have 0 rows

tutorial ptable