Query Targets

PostgreSQL
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Query Targets

Target Evaluation

Check for an exact match with the target.
Try to coerce the expression directly to the target type if necessary.
If the target is a fixed-length type (e.g. char or varchar declared with a length) then try to find a sizing function of the same name as the type taking two arguments, the first the type name and the second an integer length.

Examples

varchar Storage

For a target column declared as varchar(4) the following query ensures that the target is sized correctly:

tgl=> CREATE TABLE vv (v varchar(4));
CREATE
tgl=> INSERT INTO vv SELECT 'abc' || 'def';
INSERT 392905 1
tgl=> SELECT * FROM vv;
  v
------
 abcd
(1 row)

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