Allow the types of parameters to PREPARE to be inferred. If a parameter's

data type is unspecified or is declared to be "unknown", the type will
be inferred from the context in which the parameter is used. This was
already possible for protocol-level prepared statements.

2 files changed, 32 insertions, 23 deletions

diff --git a/src/test/regress/expected/prepare.out b/src/test/regress/expected/prepare.out
index 54616199b6..f7d1a75814 100644
--- a/src/test/regress/expected/prepare.out
+++ b/src/test/regress/expected/prepare.out
@@ -58,14 +58,6 @@ SELECT name, statement, parameter_types FROM pg_prepared_statements;
 PREPARE q2(text) AS
 	SELECT datname, datistemplate, datallowconn
 	FROM pg_database WHERE datname = $1;
-SELECT name, statement, parameter_types FROM pg_prepared_statements;
- name |                                               statement                                                | parameter_types 
-------+--------------------------------------------------------------------------------------------------------+-----------------
- q2   | PREPARE q2(text) AS
-	SELECT datname, datistemplate, datallowconn
-	FROM pg_database WHERE datname = $1; | {25}
-(1 row)
-
 EXECUTE q2('regression');
   datname   | datistemplate | datallowconn 
 ------------+---------------+--------------
@@ -75,17 +67,6 @@ EXECUTE q2('regression');
 PREPARE q3(text, int, float, boolean, oid, smallint) AS
 	SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR
 	ten = $3::bigint OR true = $4 OR oid = $5 OR odd = $6::int);
-SELECT name, statement, parameter_types FROM pg_prepared_statements;
- name |                                                                                    statement                                                                                    |   parameter_types    
-------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------
- q2   | PREPARE q2(text) AS
-	SELECT datname, datistemplate, datallowconn
-	FROM pg_database WHERE datname = $1;                                                                          | {25}
- q3   | PREPARE q3(text, int, float, boolean, oid, smallint) AS
-	SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR
-	ten = $3::bigint OR true = $4 OR oid = $5 OR odd = $6::int); | {25,23,701,16,26,21}
-(2 rows)
-
 EXECUTE q3('AAAAxx', 5::smallint, 10.5::float, false, 500::oid, 4::bigint);
  unique1 | unique2 | two | four | ten | twenty | hundred | thousand | twothousand | fivethous | tenthous | odd | even | stringu1 | stringu2 | string4 
 ---------+---------+-----+------+-----+--------+---------+----------+-------------+-----------+----------+-----+------+----------+----------+---------
@@ -160,3 +141,26 @@ SELECT * FROM q5_prep_results;
     5905 |    9537 |   1 |    1 |   5 |      5 |       5 |      905 |        1905 |       905 |     5905 |  10 |   11 | DTAAAA   | VCOAAA   | HHHHxx
 (16 rows)
 
+-- unknown or unspecified parameter types: should succeed
+PREPARE q6 AS
+    SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;
+PREPARE q7(unknown) AS
+    SELECT * FROM road WHERE thepath = $1;
+SELECT name, statement, parameter_types FROM pg_prepared_statements
+    ORDER BY name;
+ name |                                                                                    statement                                                                                    |   parameter_types    
+------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------
+ q2   | PREPARE q2(text) AS
+	SELECT datname, datistemplate, datallowconn
+	FROM pg_database WHERE datname = $1;                                                                          | {25}
+ q3   | PREPARE q3(text, int, float, boolean, oid, smallint) AS
+	SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR
+	ten = $3::bigint OR true = $4 OR oid = $5 OR odd = $6::int); | {25,23,701,16,26,21}
+ q5   | PREPARE q5(int, text) AS
+	SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2;                                                                                              | {23,25}
+ q6   | PREPARE q6 AS
+    SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;                                                                                                     | {23,19}
+ q7   | PREPARE q7(unknown) AS
+    SELECT * FROM road WHERE thepath = $1;                                                                                                               | {602}
+(5 rows)
+
diff --git a/src/test/regress/sql/prepare.sql b/src/test/regress/sql/prepare.sql
index 95db2a0910..d42b7a0879 100644
--- a/src/test/regress/sql/prepare.sql
+++ b/src/test/regress/sql/prepare.sql
@@ -34,16 +34,12 @@ PREPARE q2(text) AS
 	SELECT datname, datistemplate, datallowconn
 	FROM pg_database WHERE datname = $1;
 
-SELECT name, statement, parameter_types FROM pg_prepared_statements;
-
 EXECUTE q2('regression');
 
 PREPARE q3(text, int, float, boolean, oid, smallint) AS
 	SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR
 	ten = $3::bigint OR true = $4 OR oid = $5 OR odd = $6::int);
 
-SELECT name, statement, parameter_types FROM pg_prepared_statements;
-
 EXECUTE q3('AAAAxx', 5::smallint, 10.5::float, false, 500::oid, 4::bigint);
 
 -- too few params
@@ -63,3 +59,12 @@ PREPARE q5(int, text) AS
 	SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2;
 CREATE TEMPORARY TABLE q5_prep_results AS EXECUTE q5(200, 'DTAAAA');
 SELECT * FROM q5_prep_results;
+
+-- unknown or unspecified parameter types: should succeed
+PREPARE q6 AS
+    SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;
+PREPARE q7(unknown) AS
+    SELECT * FROM road WHERE thepath = $1;
+
+SELECT name, statement, parameter_types FROM pg_prepared_statements
+    ORDER BY name;