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copied!<p>This is more related to the type of the column value, not how the column is selected. This information is stored in <a href="http://java.sun.com/javase/6/docs/api/java/sql/DatabaseMetaData.html#getTypeInfo%28%29" rel="nofollow noreferrer"><code>DatabaseMetaData#getTypeInfo()</code></a>. The column <code>SEARCHABLE</code> can return either <a href="http://java.sun.com/javase/6/docs/api/java/sql/DatabaseMetaData.html#typePredNone" rel="nofollow noreferrer"><code>DatabaseMetaData.typePredNone</code></a> (not searchable) or other values.</p> <blockquote> <p>9: <strong>SEARCHABLE</strong> short => can you use <code>"WHERE"</code> based on this type:</p> <ul> <li><code>typePredNone</code> - No support</li> <li><code>typePredChar</code> - Only supported with <code>WHERE .. LIKE</code></li> <li><code>typePredBasic</code> - Supported except for <code>WHERE .. LIKE</code></li> <li><code>typeSearchable</code> - Supported for all <code>WHERE ..</code> </li> </ul> </blockquote> <p>Here's a snippet which displays this information:</p> <pre><code>DatabaseMetaData databaseMetaData = connection.getMetaData(); ResultSet typeInfo = databaseMetaData.getTypeInfo(); System.out.println("type name | data type | searchable"); System.out.println("-------------------------------+-----------+------------"); while (typeInfo.next()) { String typeName = typeInfo.getString("TYPE_NAME"); int dataType = typeInfo.getInt("DATA_TYPE"); boolean searchable = typeInfo.getShort("SEARCHABLE") != DatabaseMetaData.typePredNone; System.out.printf("%-30s | %-9d | %-9s%n", typeName , dataType, searchable); } </code></pre> <p>This yields something like following on a PostgreSQL 8.4 connection:</p> <pre> type name | data type | searchable -------------------------------+-----------+------------ bool | -7 | true bytea | -2 | true char | 1 | true name | 12 | true int8 | -5 | true bigserial | -5 | true int2 | 5 | true int2vector | 1111 | true int4 | 4 | true serial | 4 | true regproc | 1111 | true text | 12 | true (*snip*, it were about 270 rows, all TRUE by the way) </pre> <p>The <code>data type</code> is correlatable with <a href="http://java.sun.com/javase/6/docs/api/java/sql/ResultSetMetaData.html#getColumnType%28int%29" rel="nofollow noreferrer"><code>ResultSetMetaData#getColumnType()</code></a>.</p>

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