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<chapter id="sql-syntax">

<title>SQL Syntax</title>

<para>

The Unicode escape syntax works only when the server encoding is

UTF8. When other server encodings are used, only code points in

the ASCII range (up to <literal>\007F</literal>) can be specified.

Both the 4-digit and the 6-digit form can be used to specify

UTF-16 surrogate pairs to compose characters with code points

larger than U+FFFF (although the availability of

the 6-digit form technically makes this unnecessary).

<literal>UTF8</>. When other server encodings are used, only code

points in the ASCII range (up to <literal>\007F</literal>) can be

specified. Both the 4-digit and the 6-digit form can be used to

specify UTF-16 surrogate pairs to compose characters with code

points larger than U+FFFF, although the availability of the

6-digit form technically makes this unnecessary. (When surrogate

pairs are used when the server encoding is <literal>UTF8</>, they

are first combined into a single code point that is then encoded

in UTF-8.)

</para>

<para>

<para>

The Unicode escape syntax works fully only when the server

encoding is UTF-8. When other server encodings are used, only

code points in the ASCII range (up to <literal>\u007F</>) can be

specified. Both the 4-digit and the 8-digit form can be used to

specify UTF-16 surrogate pairs to compose characters with code

points larger than U+FFFF (although the

availability of the 8-digit form technically makes this

unnecessary).

encoding is <literal>UTF8</>. When other server encodings are

used, only code points in the ASCII range (up

to <literal>\u007F</>) can be specified. Both the 4-digit and

the 8-digit form can be used to specify UTF-16 surrogate pairs to

compose characters with code points larger than U+FFFF, although

the availability of the 8-digit form technically makes this

unnecessary. (When surrogate pairs are used when the server

encoding is <literal>UTF8</>, they are first combined into a

single code point that is then encoded in UTF-8.)

</para>

<caution>

<para>

The Unicode escape syntax works only when the server encoding is

UTF8. When other server encodings are used, only code points in

the ASCII range (up to <literal>\007F</literal>) can be

specified.

Both the 4-digit and the 6-digit form can be used to specify

UTF-16 surrogate pairs to compose characters with code points

larger than U+FFFF (although the availability

of the 6-digit form technically makes this unnecessary).

<literal>UTF8</>. When other server encodings are used, only

code points in the ASCII range (up to <literal>\007F</literal>)

can be specified. Both the 4-digit and the 6-digit form can be

used to specify UTF-16 surrogate pairs to compose characters with

code points larger than U+FFFF, although the availability of the

6-digit form technically makes this unnecessary. (When surrogate

pairs are used when the server encoding is <literal>UTF8</>, they

are first combined into a single code point that is then encoded

in UTF-8.)

</para>

<para>