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<refentry id="SQL-CREATECAST">

<refmeta>

the same name as a data type, returned that data type, and took one

argument of a different type was automatically a cast function.

This convention has been abandoned in face of the introduction of

schemas and to be able to represent binary compatible casts in the

schemas and to be able to represent binary-coercible casts in the

system catalogs. The built-in cast functions still follow this naming

scheme, but they have to be shown as casts in the system catalog

<structname>pg_cast</> as well.

exactly match any existing function, but <replaceable>name</> is the name

of a data type and <structname>pg_cast</> provides a binary-coercible cast

to this type from the type of <replaceable>x</>, then the call will be

construed as a binary-compatible cast. This exception is made so that

construed as a binary-coercible cast. This exception is made so that

binary-coercible casts can be invoked using functional syntax, even

though they lack any function. Likewise, if there is no

<structname>pg_cast</> entry but the cast would be to or from a string