Move edge conditions to separate test case.

Added regression test case for bug 1195735 once it gets fixed.
Increased coverage of permutations to basic test case.

mysql-test/suite/oqgraph/boundary_conditions.test

+--disable_warnings
+DROP TABLE IF EXISTS graph_base;
+DROP TABLE IF EXISTS graph;
+DROP TABLE IF EXISTS graph2;
+--enable_warnings
+
+CREATE TABLE graph2 (
+    latch   VARCHAR(32) NULL,
+    origid  BIGINT    UNSIGNED NULL,
+    destid  BIGINT    UNSIGNED NULL,
+    weight  DOUBLE    NULL,
+    seq     BIGINT    UNSIGNED NULL,
+    linkid  BIGINT    UNSIGNED NULL,
+    KEY (latch, origid, destid) USING HASH,
+    KEY (latch, destid, origid) USING HASH
+  ) ENGINE=OQGRAPH DATA_TABLE='graph_base' ORIGID='from_id', DESTID='to_id';
+# Because the backing store graph_base doesnt exist yet, the select should fail  
+--error S42S02
+SELECT * FROM graph2 WHERE latch='dijkstras' AND origid=1 AND destid=6;
+DROP TABLE graph2;
+
+# Create the backing store
+CREATE TABLE graph_base (
+    from_id INT UNSIGNED NOT NULL,
+    to_id INT UNSIGNED NOT NULL,
+    PRIMARY KEY (from_id,to_id),
+    INDEX (to_id)
+  ) ENGINE=MyISAM;
+
+
+CREATE TABLE graph (
+    latch   VARCHAR(32) NULL,
+    origid  BIGINT    UNSIGNED NULL,
+    destid  BIGINT    UNSIGNED NULL,
+    weight  DOUBLE    NULL,
+    seq     BIGINT    UNSIGNED NULL,
+    linkid  BIGINT    UNSIGNED NULL,
+    KEY (latch, origid, destid) USING HASH,
+    KEY (latch, destid, origid) USING HASH
+  ) ENGINE=OQGRAPH DATA_TABLE='graph_base' ORIGID='from_id', DESTID='to_id';
+
+
+INSERT INTO graph_base(from_id, to_id) VALUES (1,2), (2,1);
+INSERT INTO graph_base(from_id, to_id) VALUES (1,3), (3,1);
+INSERT INTO graph_base(from_id, to_id) VALUES (3,4), (4,3);
+INSERT INTO graph_base(from_id, to_id) VALUES (5,6), (6,5);
+
+--echo # No Search/0 - result should return same rows as inserted for origid,destid,weight
+--echo # FIXME - THIS CODE IS CURRENTLY BROKEN - see https://bugs.launchpad.net/oqgraph/+bug/1195778
+SELECT * FROM graph WHERE latch='no_search';
+SELECT * FROM graph WHERE latch='no_search' and destid=2 and origid=1;
+SELECT * FROM graph WHERE latch='no_search' and origid=1;
+SELECT * FROM graph WHERE latch='no_search' and destid=1;
+SELECT * FROM graph WHERE latch='no_search' and origid=666;
+SELECT * FROM graph WHERE latch='no_search' and origid=NULL;
+SELECT * FROM graph WHERE latch='0' ;
+SELECT * FROM graph WHERE latch='0' and destid=2 and origid=1;
+SELECT * FROM graph WHERE latch='0' and origid=1;
+SELECT * FROM graph WHERE latch='0' and destid=1;
+SELECT * FROM graph WHERE latch='0' and origid=666;
+SELECT * FROM graph WHERE latch='0' and origid=NULL;
+
+--echo # Expect no result, because of autocast
+SELECT * FROM graph WHERE latch=1 ;
+SELECT * FROM graph WHERE latch=1 and destid=2 and origid=1;
+SELECT * FROM graph WHERE latch=1 and origid=1;
+SELECT * FROM graph WHERE latch=1 and destid=1;
+SELECT * FROM graph WHERE latch=1 and origid=666;
+SELECT * FROM graph WHERE latch=1 and origid=NULL;
+SELECT * FROM graph WHERE latch=2 ;
+SELECT * FROM graph WHERE latch=2 and destid=2 and origid=1;
+SELECT * FROM graph WHERE latch=2 and origid=1;
+SELECT * FROM graph WHERE latch=2 and destid=1;
+SELECT * FROM graph WHERE latch=2 and origid=666;
+SELECT * FROM graph WHERE latch=2 and origid=NULL;
+
+--echo # Should this return an error? it seems we treat it as just another bogus latch
+SELECT * FROM graph WHERE latch='ThisExceeds32Characters456789012';
+--echo # Expect no result, because of invalid latch
+SELECT * FROM graph WHERE latch='bogus';
+SELECT * FROM graph WHERE latch='bogus' and destid=2 and origid=1;
+SELECT * FROM graph WHERE latch='bogus' and origid=1;
+SELECT * FROM graph WHERE latch='bogus' and destid=1;
+SELECT * FROM graph WHERE latch='bogus' and origid=666;
+SELECT * FROM graph WHERE latch='bogus' and origid=NULL;
+#-- Note the next line couter-intuitively produces no warning
+SELECT * FROM graph WHERE latch='666';
+SELECT * FROM graph WHERE latch='666' and destid=2 and origid=1;
+SELECT * FROM graph WHERE latch='666' and origid=1;
+SELECT * FROM graph WHERE latch='666' and destid=1;
+SELECT * FROM graph WHERE latch='666' and origid=666;
+#-- Note the next line couter-intuitively produces no warning
+SELECT * FROM graph WHERE latch='666' and origid=NULL;
+SELECT * FROM graph WHERE latch='-1';
+SELECT * FROM graph WHERE latch='-1' and destid=2 and origid=1;
+SELECT * FROM graph WHERE latch='-1' and origid=1;
+SELECT * FROM graph WHERE latch='-1' and destid=1;
+SELECT * FROM graph WHERE latch='-1' and origid=666;
+SELECT * FROM graph WHERE latch='-1' and origid=NULL;
+
+--echo # Make sure we dont crash if someone passed in a UTF string
+#-- Note the next line couter-intuitively produces no warning
+SELECT * FROM graph WHERE latch='Ω Ohms Tennis Ball 〄';
+SELECT * FROM graph WHERE latch='Ω Ohms Tennis Ball 〄' and destid=2 and origid=1;
+SELECT * FROM graph WHERE latch='Ω Ohms Tennis Ball 〄' and origid=1;
+SELECT * FROM graph WHERE latch='Ω Ohms Tennis Ball 〄' and destid=1;
+SELECT * FROM graph WHERE latch='Ω Ohms Tennis Ball 〄' and origid=666;
+#-- Note the next line couter-intuitively produces no warning
+SELECT * FROM graph WHERE latch='Ω Ohms Tennis Ball 〄' and origid=NULL;
+
+--echo # Expect no result, because of autocast and deprecated syntax
+--echo # Allows 0 and NULL to have same effect
+#-- Note the next line couter-intuitively produces no warning
+SELECT * FROM graph WHERE latch=0;        
+SELECT * FROM graph WHERE latch=0 and destid=2 and origid=1;
+SELECT * FROM graph WHERE latch=0 and origid=1;
+SELECT * FROM graph WHERE latch=0 and destid=1;
+SELECT * FROM graph WHERE latch=0 and origid=666;
+#-- Note the next line couter-intuitively produces no warning
+SELECT * FROM graph WHERE latch=0 and origid=NULL;
+
+--echo # Expect no result, because of NULL latch
+SELECT * FROM graph WHERE latch=NULL;
+SELECT * FROM graph WHERE latch=NULL and destid=2 and origid=1;
+SELECT * FROM graph WHERE latch=NULL and origid=1;
+SELECT * FROM graph WHERE latch=NULL and destid=1;
+SELECT * FROM graph WHERE latch=NULL and origid=666;
+SELECT * FROM graph WHERE latch=NULL and origid=NULL;
+
+--echo # With no latch, original data in origid and destid columns
+#-- Note, weight==1 in this case
+SELECT * FROM graph;
+SELECT * FROM graph WHERE destid=2 and origid=1;
+SELECT * FROM graph WHERE origid=1;
+SELECT * FROM graph WHERE destid=1;
+SELECT * FROM graph WHERE origid=666;
+SELECT * FROM graph WHERE origid=NULL;
+
+#-- what happens if we have two links the same?
+--error 1062
+INSERT INTO graph_base(from_id, to_id) VALUES (1,2);
+
+DELETE FROM graph_base;
+#-- Uncomment the following after fixing https://bugs.launchpad.net/oqgraph/+bug/1195735
+#-- FIXME SELECT * FROM graph;
+
+FLUSH TABLES;
+
+TRUNCATE TABLE graph_base;
+#-- Uncomment the following after fixing https://bugs.launchpad.net/oqgraph/+bug/xxxxxxx - Causes the later select to not fail!
+#-- For now dont report a separate bug as it may be a manifestation of https://bugs.launchpad.net/oqgraph/+bug/1195735
+#-- FIXME SELECT * FROM graph;
+
+#-- Expect error if we pull the table out from under
+DROP TABLE graph_base;
+
+--error S42S02
+SELECT * FROM graph WHERE latch='dijkstras' AND origid=1 AND destid=6;
+
+DROP TABLE graph;
+

mysql-test/suite/oqgraph/regression_1195735.test

+# Regression test for https://bugs.launchpad.net/oqgraph/+bug/1195735
+#--reproduce bug where select * from graph after delete from graph_base hangs the server
+--disable_warnings
+DROP TABLE IF EXISTS graph_base;
+DROP TABLE IF EXISTS graph;
+--enable_warnings
+
+# Create the backing store
+CREATE TABLE graph_base (
+    from_id INT UNSIGNED NOT NULL,
+    to_id INT UNSIGNED NOT NULL,
+    PRIMARY KEY (from_id,to_id),
+    INDEX (to_id)
+  ) ENGINE=MyISAM;
+
+
+CREATE TABLE graph (
+    latch   VARCHAR(32) NULL,
+    origid  BIGINT    UNSIGNED NULL,
+    destid  BIGINT    UNSIGNED NULL,
+    weight  DOUBLE    NULL,
+    seq     BIGINT    UNSIGNED NULL,
+    linkid  BIGINT    UNSIGNED NULL,
+    KEY (latch, origid, destid) USING HASH,
+    KEY (latch, destid, origid) USING HASH
+  ) ENGINE=OQGRAPH DATA_TABLE='graph_base' ORIGID='from_id', DESTID='to_id';
+
+
+INSERT INTO graph_base(from_id, to_id) VALUES (1,2), (2,1);
+
+--echo One select of any clauses at all on graph here caused a hang on the select after the DELETE FROM
+#-- even this if it is the only one - but it doesnt hang here ... SELECT * FROM graph;
+SELECT * FROM graph WHERE destid=2 and origid=1;
+
+DELETE FROM graph_base;
+#-- Bug 1195735 hangs on the next line
+SELECT * from graph;
+FLUSH TABLES;
+TRUNCATE TABLE graph_base;
+DROP TABLE graph_base;
+--error S42S02
+SELECT * FROM graph WHERE latch='dijkstras' AND origid=1 AND destid=6;
+DROP TABLE graph;
+