Oracle 5.0 Reference Manual page 806

Suppose that column
X
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Suppose also that the column values are retrieved using the following statement:
SELECT X FROM T ORDER BY X COLLATE collation_name;
The following table shows the resulting order of the values if we use
latin1_swedish_ci
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The character that causes the different sort orders in this example is the U with two dots over it (ü),
which the Germans call "U-umlaut."
• The first column shows the result of the
that U-umlaut sorts with Y.
• The second column shows the result of the
umlaut sorts with U.
• The third column shows the result of the
umlaut sorts with UE.
Example 2: Searching for German Umlauts
Suppose that you have three tables that differ only by the character set and collation used:
mysql> SET NAMES utf8;
mysql> CREATE TABLE german1 (
-> c CHAR(10)
-> ) CHARACTER SET latin1 COLLATE latin1_german1_ci;
mysql> CREATE TABLE german2 (
-> c CHAR(10)
-> ) CHARACTER SET latin1 COLLATE latin1_german2_ci;
mysql> CREATE TABLE germanutf8 (
-> c CHAR(10)
-> ) CHARACTER SET utf8 COLLATE utf8_unicode_ci;
Each table contains two records:
mysql> INSERT INTO german1 VALUES ('Bar'), ('Bär');
mysql> INSERT INTO german2 VALUES ('Bar'), ('Bär');
mysql> INSERT INTO germanutf8 VALUES ('Bar'), ('Bär');
Two of the above collations have an
(latin1_german2_ci). For that reason, you'll get these results in comparisons:
mysql> SELECT * FROM german1 WHERE c = 'Bär';
+------+
| c |
+------+
| Bar |
| Bär |
+------+
mysql> SELECT * FROM german2 WHERE c = 'Bär';
+------+
| c |
+------+
Collation Issues
in table has these
T latin1
latin1_german1_ci
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SELECT
SELECT
SELECT
equality, and one has no such equality
A = Ä
786
column values:
ORDER BY
latin1_german2_ci
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using the Swedish/Finnish collating rule, which says
using the German DIN-1 rule, which says that U-
using the German DIN-2 rule, which says that U-
with different collations.