PostgreSQL User's Guide
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# Query Targets

Target Evaluation

1. Check for an exact match with the target.

2. Try to coerce the expression directly to the target type if necessary.

3. 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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