[informix-sql] Support of set deferred_prepare statement (#3889)

Author: hellozrh

sql/informix-sql/InformixSQLLexer.g4

@@ -82,6 +82,7 @@ DATASKIP          : 'DATASKIP';
 DEFAULT           : 'DEFAULT';
 DEFERRABLE        : 'DEFERRABLE';
 DEFERRED          : 'DEFERRED';
+DEFERRED_PREPARE  : 'DEFERRED_PREPARE';
 DELETE            : 'DELETE';
 DEBUG             : 'DEBUG';
 DESC              : 'DESC';

sql/informix-sql/InformixSQLParser.g4

@@ -73,6 +73,7 @@ unitStatement
         | setCollation
         | setDataskip
         | setDebugFile
+        | setDeferredPrepareStatement
     ) SCOL
     ;
 
@@ -251,6 +252,11 @@ setDebugFile
     : SET DEBUG FILE TO (CHAR_STRING | identifier) (WITH APPEND)?
     ;
 
+// https://www.ibm.com/docs/en/informix-servers/14.10?topic=statements-set-deferred-prepare-statement
+setDeferredPrepareStatement
+    : SET DEFERRED_PREPARE (ENABLED | DISABLED)?
+    ;
+
 quotedString
     : CHAR_STRING
     ;
@@ -311,6 +317,7 @@ keyword
     | DEFAULT
     | DEFERRABLE
     | DEFERRED
+    | DEFERRED_PREPARE
     | DELETE
     | DESC
     | DETACH

sql/informix-sql/examples/set_deferred_prepare.sql

@@ -0,0 +1,3 @@
+set deferred_prepare;
+set deferred_prepare enabled;
+set deferred_prepare DISABLED;