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diff --git a/test/alterdropcol2.test b/test/alterdropcol2.test
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+# 2021 February 19
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#*************************************************************************
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix alterdropcol2
+
+# If SQLITE_OMIT_ALTERTABLE is defined, omit this file.
+ifcapable !altertable {
+  finish_test
+  return
+}
+
+# EVIDENCE-OF: R-58318-35349 The DROP COLUMN syntax is used to remove an
+# existing column from a table.
+do_execsql_test 1.0 {
+  CREATE TABLE t1(c, b, a, PRIMARY KEY(b, a)) WITHOUT ROWID;
+  INSERT INTO t1 VALUES(1, 2, 3), (4, 5, 6);
+}
+do_execsql_test 1.1 {
+  ALTER TABLE t1 DROP c;
+}
+
+# EVIDENCE-OF: The DROP COLUMN command removes the named column from the table,
+# and also rewrites the entire table to purge the data associated with that
+# column.  
+do_execsql_test 1.2.1 {
+  SELECT * FROM t1;
+} {2 3   5 6}
+
+do_execsql_test 1.2.2 {
+  SELECT sql FROM sqlite_schema;
+} {
+  {CREATE TABLE t1(b, a, PRIMARY KEY(b, a)) WITHOUT ROWID}
+}
+
+proc do_atdc_error_test {tn schema atdc error} {
+  reset_db
+  execsql $schema
+  uplevel [list do_catchsql_test $tn $atdc [list 1 [string trim $error]]]
+}
+
+#-------------------------------------------------------------------------
+# Test cases 2.* attempt to verify the following:
+#
+# EVIDENCE-OF: R-24098-10282 The DROP COLUMN command only works if the column
+# is not referenced by any other parts of the schema and is not a PRIMARY KEY
+# and does not have a UNIQUE constraint.
+#
+
+# EVIDENCE-OF: R-52436-31752 The column is a PRIMARY KEY or part of one.
+#
+do_atdc_error_test 2.1.1 {
+  CREATE TABLE x1(a PRIMARY KEY, b, c);
+} { 
+  ALTER TABLE x1 DROP COLUMN a 
+} {
+  cannot drop PRIMARY KEY column: "a"
+}
+do_atdc_error_test 2.1.2 {
+  CREATE TABLE x1(a,b,c,d,e, PRIMARY KEY(b,c,d));
+} { 
+  ALTER TABLE x1 DROP COLUMN c
+} {
+  cannot drop PRIMARY KEY column: "c"
+}
+
+# EVIDENCE-OF: R-43412-16016 The column has a UNIQUE constraint.
+#
+do_atdc_error_test 2.2.1 {
+  CREATE TABLE x1(a PRIMARY KEY, b, c UNIQUE);
+} { 
+  ALTER TABLE x1 DROP COLUMN c 
+} {
+  cannot drop UNIQUE column: "c"
+}
+do_atdc_error_test 2.2.2 {
+  CREATE TABLE x1(a PRIMARY KEY, b, c, UNIQUE(b, c));
+} { 
+  ALTER TABLE x1 DROP COLUMN c 
+} {
+  error in table x1 after drop column: no such column: c
+}
+
+# EVIDENCE-OF: R-46731-08965 The column is indexed.
+#
+do_atdc_error_test 2.3.1 {
+  CREATE TABLE 'one two'('x y', 'z 1', 'a b');
+  CREATE INDEX idx ON 'one two'('z 1');
+} { 
+  ALTER TABLE 'one two' DROP COLUMN 'z 1' 
+} {
+  error in index idx after drop column: no such column: z 1
+}
+do_atdc_error_test 2.3.2 {
+  CREATE TABLE x1(a, b, c);
+  CREATE INDEX idx ON x1(a);
+} { 
+  ALTER TABLE x1 DROP COLUMN a;
+} {
+  error in index idx after drop column: no such column: a
+}
+
+# EVIDENCE-OF: R-46731-08965 The column is indexed.
+#
+do_atdc_error_test 2.4.1 {
+  CREATE TABLE x1234(a, b, c PRIMARY KEY) WITHOUT ROWID;
+  CREATE INDEX i1 ON x1234(b) WHERE ((a+5) % 10)==0;
+} { 
+  ALTER TABLE x1234 DROP a
+} {
+  error in index i1 after drop column: no such column: a
+}
+
+# EVIDENCE-OF: R-47838-03249 The column is named in a table or column
+# CHECK constraint not associated with the column being dropped.
+#
+do_atdc_error_test 2.5.1 {
+  CREATE TABLE x1234(a, b, c PRIMARY KEY, CHECK(((a+5)%10)!=0)) WITHOUT ROWID;
+} { 
+  ALTER TABLE x1234 DROP a
+} {
+  error in table x1234 after drop column: no such column: a
+}
+
+# EVIDENCE-OF: R-55640-01652 The column is used in a foreign key constraint.
+#
+do_atdc_error_test 2.6.1 {
+  CREATE TABLE p1(x, y UNIQUE);
+  CREATE TABLE c1(u, v, FOREIGN KEY (v) REFERENCES p1(y))
+} { 
+  ALTER TABLE c1 DROP v
+} {
+  error in table c1 after drop column: unknown column "v" in foreign key definition
+}
+
+# EVIDENCE-OF: R-20795-39479 The column is used in the expression of a 
+# generated column.
+do_atdc_error_test 2.7.1 {
+  CREATE TABLE c1(u, v, w AS (u+v));
+} { 
+  ALTER TABLE c1 DROP v
+} {
+  error in table c1 after drop column: no such column: v
+}
+do_atdc_error_test 2.7.2 {
+  CREATE TABLE c1(u, v, w AS (u+v) STORED);
+} { 
+  ALTER TABLE c1 DROP u
+} {
+  error in table c1 after drop column: no such column: u
+}
+
+# EVIDENCE-OF: R-01515-49025 The column appears in a trigger or view.
+#
+do_atdc_error_test 2.8.1 {
+  CREATE TABLE log(l);
+  CREATE TABLE c1(u, v, w);
+  CREATE TRIGGER tr1 AFTER INSERT ON c1 BEGIN
+    INSERT INTO log VALUES(new.w);
+  END;
+} { 
+  ALTER TABLE c1 DROP w
+} {
+  error in trigger tr1 after drop column: no such column: new.w
+}
+do_atdc_error_test 2.8.2 {
+  CREATE TABLE c1(u, v, w);
+  CREATE VIEW v1 AS SELECT u, v, w FROM c1;
+} { 
+  ALTER TABLE c1 DROP w
+} {
+  error in view v1 after drop column: no such column: w
+}
+do_atdc_error_test 2.8.3 {
+  CREATE TABLE c1(u, v, w);
+  CREATE VIEW v1 AS SELECT * FROM c1 WHERE w IS NOT NULL;
+} { 
+  ALTER TABLE c1 DROP w
+} {
+  error in view v1 after drop column: no such column: w
+}
+
+#-------------------------------------------------------------------------
+# Verify that a column that is part of a CHECK constraint may be dropped
+# if the CHECK constraint was specified as part of the column definition.
+#
+
+# STALE-EVIDENCE: R-60924-11170 However, the column being deleted can be used in a
+# column CHECK constraint because the column CHECK constraint is dropped
+# together with the column itself.
+do_execsql_test 3.0 {
+  CREATE TABLE yyy(q, w, e CHECK (e > 0), r);
+  INSERT INTO yyy VALUES(1,1,1,1), (2,2,2,2);
+
+  CREATE TABLE zzz(q, w, e, r, CHECK (e > 0));
+  INSERT INTO zzz VALUES(1,1,1,1), (2,2,2,2);
+}
+do_catchsql_test 3.1.1 {
+  INSERT INTO yyy VALUES(0,0,0,0);
+} {1 {CHECK constraint failed: e > 0}}
+do_catchsql_test 3.1.2 {
+  INSERT INTO yyy VALUES(0,0,0,0);
+} {1 {CHECK constraint failed: e > 0}}
+
+do_execsql_test 3.2.1 {
+  ALTER TABLE yyy DROP e;
+}
+do_catchsql_test 3.2.2 {
+  ALTER TABLE zzz DROP e;
+} {1 {error in table zzz after drop column: no such column: e}}
+
+finish_test