dblink_build_sql_delete#
dblink_build_sql_delete
dblink_build_sql_delete — builds a DELETE statement using supplied values for primary key field values
Синтаксис
dblink_build_sql_delete(text relname,
int2vector primary_key_attnums,
integer num_primary_key_atts,
text[] tgt_pk_att_vals_array) returns text
Description
dblink_build_sql_delete can be useful in doing selective
replication of a local table to a remote database. It builds an SQL
DELETE command that will delete the row with the given
primary key values.
Arguments
relnameName of a local relation, for example
fooormyschema.mytab. Include double quotes if the name is mixed-case or contains special characters, for example"FooBar"; without quotes, the string will be folded to lower case.primary_key_attnumsAttribute numbers (1-based) of the primary key fields, for example
1 2.num_primary_key_attsThe number of primary key fields.
tgt_pk_att_vals_arrayValues of the primary key fields to be used in the resulting
DELETEcommand. Each field is represented in text form.
Return Value
Returns the requested SQL statement as text.
Notes
As of PostgreSQL 9.0, the attribute numbers in
primary_key_attnums are interpreted as logical
column numbers, corresponding to the column's position in
SELECT * FROM relname. Previous versions interpreted the
numbers as physical column positions. There is a difference if any
column(s) to the left of the indicated column have been dropped during
the lifetime of the table.
Examples
SELECT dblink_build_sql_delete('"MyFoo"', '1 2', 2, '{"1", "b"}');
dblink_build_sql_delete
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DELETE FROM "MyFoo" WHERE f1='1' AND f2='b'
(1 row)