progress 4gl - Static vs dynamic queries in OpenEdge -


question common, let's see pros , cons of each in openedge in terms of code readability, flexibility , performance off course.

static queries:

+   readability: convenient `buffer.field` notation +   performance: higher (supposedly, need comments) -/+ "global scope" allows handle used buffers, lead                  ambiguousness, you'll have clarify table                  name (table.field instead of field) -   flexibility: cannot alternate predicate-expression much,                  if function not recommended (can affect performance)

dynamic queries: 

+   flexibility: can build predicate-expression runtime +   flexibility: can work each field not specifying name,                  f.e. can process fields of record in cycle +   flexibility: reusable (need comments on point) +/- "local scope" allows use buffers specified in `set-buffers` method -   readability: little more code write -   performance: slower (not sure)

additions , corrections welcome. links related read.

a static query's filter condition can changed "on fly" so:

define query q-name table-name. define variable h-qry   handle      no-undo. h-qry = query q-name:handle. h-qry:query-prepare("for each table-name table-name.field-name = 1").

from here query treated same normal static query.

readability: "buffer-handle:buffer-field("field-name"):buffer-value" construct refers dynamic buffers - it's acceptable use static buffers in dynamic queries (via buffer table-name:handle), dynamic query buffers can used w/static buffers , it's not necessary de-reference field using it's handle.

performance: last time did comparison, dynamic queries slower static queries same query condition. upside they're more flexible static queries.

reusability: once dynamic query's buffer structure has been set, afaik, can't changed. can re-opened new filter condition same static query though.


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