static void FKLookupParent(Parse parse, int db, Table table, Index index, FKey fkey, int[] cols, int regDataId, int incr, bool isIgnore)
{
Vdbe v = parse.GetVdbe(); // Vdbe to add code to
int curId = parse.Tabs - 1; // Cursor number to use
int okId = v.MakeLabel(); // jump here if parent key found
// If nIncr is less than zero, then check at runtime if there are any outstanding constraints to resolve. If there are not, there is no need
// to check if deleting this row resolves any outstanding violations.
//
// Check if any of the key columns in the child table row are NULL. If any are, then the constraint is considered satisfied. No need to
// search for a matching row in the parent table.
int i;
if (incr < 0)
{
v.AddOp2(OP.FkIfZero, fkey.IsDeferred, okId);
}
for (i = 0; i < fkey.Cols.length; i++)
{
int regId = cols[i] + regDataId + 1;
v.AddOp2(OP.IsNull, regId, okId);
}
if (!isIgnore)
{
if (index == null)
{
// If pIdx is NULL, then the parent key is the INTEGER PRIMARY KEY column of the parent table (table pTab).
int mustBeIntId; // Address of MustBeInt instruction
int regTempId = parse.GetTempReg();
// Invoke MustBeInt to coerce the child key value to an integer (i.e. apply the affinity of the parent key). If this fails, then there
// is no matching parent key. Before using MustBeInt, make a copy of the value. Otherwise, the value inserted into the child key column
// will have INTEGER affinity applied to it, which may not be correct.
v.AddOp2(OP.SCopy, cols[0] + 1 + regDataId, regTempId);
mustBeIntId = v.AddOp2(OP.MustBeInt, regTempId, 0);
// If the parent table is the same as the child table, and we are about to increment the constraint-counter (i.e. this is an INSERT operation),
// then check if the row being inserted matches itself. If so, do not increment the constraint-counter.
if (table == fkey.From && incr == 1)
{
v.AddOp3(OP.Eq, regDataId, okId, regTempId);
}
parse.OpenTable(parse, curId, db, table, OP.OpenRead);
v.AddOp3(OP.NotExists, curId, 0, regTempId);
v.AddOp2(OP.Goto, 0, okId);
v.JumpHere(v.CurrentAddr() - 2);
v.JumpHere(mustBeIntId);
parse.ReleaseTempReg(regTempId);
}
else
{
int colsLength = fkey.Cols.length;
int regTempId = parse.GetTempRange(colsLength);
int regRecId = parse.GetTempReg();
KeyInfo key = IndexKeyinfo(parse, index);
v.AddOp3(OP.OpenRead, curId, index.Id, db);
v.ChangeP4(v, -1, key, Vdbe.P4T.KEYINFO_HANDOFF);
for (i = 0; i < colsLength; i++)
{
v.AddOp2(OP.Copy, cols[i] + 1 + regDataId, regTempId + i);
}
// If the parent table is the same as the child table, and we are about to increment the constraint-counter (i.e. this is an INSERT operation),
// then check if the row being inserted matches itself. If so, do not increment the constraint-counter.
// If any of the parent-key values are NULL, then the row cannot match itself. So set JUMPIFNULL to make sure we do the OP_Found if any
// of the parent-key values are NULL (at this point it is known that none of the child key values are).
if (table == fkey.From && incr == 1)
{
int jumpId = v.CurrentAddr() + colsLength + 1;
for (i = 0; i < colsLength; i++)
{
int childId = cols[i] + 1 + regDataId;
int parentId = index.Columns[i] + 1 + regDataId;
Debug.Assert(cols[i] != table.PKey);
if (index.Columns[i] == table.PKey)
{
parentId = regDataId; // The parent key is a composite key that includes the IPK column
}
v.AddOp3(OP.Ne, childId, jumpId, parentId);
v.ChangeP5(SQLITE_JUMPIFNULL);
}
v.AddOp2(OP.Goto, 0, okId);
}
v.AddOp3(OP.MakeRecord, regTempId, colsLength, regRecId);
v.ChangeP4(-1, IndexAffinityStr(v, index), Vdbe.P4T.TRANSIENT);
v.AddOp4Int(OP.Found, curId, okId, regRecId, 0);
parse.ReleaseTempReg(regRecId);
parse.ReleaseTempRange(regTempId, colsLength);
}
}
if (!fkey.IsDeferred && parse.Toplevel == null && parse.IsMultiWrite == 0)
{
// Special case: If this is an INSERT statement that will insert exactly one row into the table, raise a constraint immediately instead of
// incrementing a counter. This is necessary as the VM code is being generated for will not open a statement transaction.
Debug.Assert(incr == 1);
HaltConstraint(parse, OE.Abort, "foreign key constraint failed", Vdbe.P4T.STATIC);
}
else
{
if (incr > 0 && !fkey.IsDeferred)
{
E.Parse_Toplevel(parse).MayAbort = true;
}
v.AddOp2(OP.FkCounter, fkey.IsDeferred, incr);
}
v.ResolveLabel(v, okId);
v.AddOp1(OP.Close, curId);
}
static void FKLookupParent(Parse parse, int db, Table table, Index index, FKey fkey, int[] cols, int regDataId, int incr, bool isIgnore)
{
Vdbe v = parse.GetVdbe(); // Vdbe to add code to
int curId = parse.Tabs - 1; // Cursor number to use
int okId = v.MakeLabel(); // jump here if parent key found
// If nIncr is less than zero, then check at runtime if there are any outstanding constraints to resolve. If there are not, there is no need
// to check if deleting this row resolves any outstanding violations.
//
// Check if any of the key columns in the child table row are NULL. If any are, then the constraint is considered satisfied. No need to
// search for a matching row in the parent table.
int i;
if (incr < 0)
v.AddOp2(OP.FkIfZero, fkey.IsDeferred, okId);
for (i = 0; i < fkey.Cols.length; i++)
{
int regId = cols[i] + regDataId + 1;
v.AddOp2(OP.IsNull, regId, okId);
}
if (!isIgnore)
{
if (index == null)
{
// If pIdx is NULL, then the parent key is the INTEGER PRIMARY KEY column of the parent table (table pTab).
int mustBeIntId; // Address of MustBeInt instruction
int regTempId = parse.GetTempReg();
// Invoke MustBeInt to coerce the child key value to an integer (i.e. apply the affinity of the parent key). If this fails, then there
// is no matching parent key. Before using MustBeInt, make a copy of the value. Otherwise, the value inserted into the child key column
// will have INTEGER affinity applied to it, which may not be correct.
v.AddOp2(OP.SCopy, cols[0] + 1 + regDataId, regTempId);
mustBeIntId = v.AddOp2(OP.MustBeInt, regTempId, 0);
// If the parent table is the same as the child table, and we are about to increment the constraint-counter (i.e. this is an INSERT operation),
// then check if the row being inserted matches itself. If so, do not increment the constraint-counter.
if (table == fkey.From && incr == 1)
v.AddOp3(OP.Eq, regDataId, okId, regTempId);
parse.OpenTable(parse, curId, db, table, OP.OpenRead);
v.AddOp3(OP.NotExists, curId, 0, regTempId);
v.AddOp2(OP.Goto, 0, okId);
v.JumpHere(v.CurrentAddr() - 2);
v.JumpHere(mustBeIntId);
parse.ReleaseTempReg(regTempId);
}
else
{
int colsLength = fkey.Cols.length;
int regTempId = parse.GetTempRange(colsLength);
int regRecId = parse.GetTempReg();
KeyInfo key = IndexKeyinfo(parse, index);
v.AddOp3(OP.OpenRead, curId, index.Id, db);
v.ChangeP4(v, -1, key, Vdbe.P4T.KEYINFO_HANDOFF);
for (i = 0; i < colsLength; i++)
v.AddOp2(OP.Copy, cols[i] + 1 + regDataId, regTempId + i);
// If the parent table is the same as the child table, and we are about to increment the constraint-counter (i.e. this is an INSERT operation),
// then check if the row being inserted matches itself. If so, do not increment the constraint-counter.
// If any of the parent-key values are NULL, then the row cannot match itself. So set JUMPIFNULL to make sure we do the OP_Found if any
// of the parent-key values are NULL (at this point it is known that none of the child key values are).
if (table == fkey.From && incr == 1)
{
int jumpId = v.CurrentAddr() + colsLength + 1;
for (i = 0; i < colsLength; i++)
{
int childId = cols[i] + 1 + regDataId;
int parentId = index.Columns[i] + 1 + regDataId;
Debug.Assert(cols[i] != table.PKey);
if (index.Columns[i] == table.PKey)
parentId = regDataId; // The parent key is a composite key that includes the IPK column
v.AddOp3(OP.Ne, childId, jumpId, parentId);
v.ChangeP5(SQLITE_JUMPIFNULL);
}
v.AddOp2(OP.Goto, 0, okId);
}
v.AddOp3(OP.MakeRecord, regTempId, colsLength, regRecId);
v.ChangeP4(-1, IndexAffinityStr(v, index), Vdbe.P4T.TRANSIENT);
v.AddOp4Int(OP.Found, curId, okId, regRecId, 0);
parse.ReleaseTempReg(regRecId);
parse.ReleaseTempRange(regTempId, colsLength);
}
}
if (!fkey.IsDeferred && parse.Toplevel == null && parse.IsMultiWrite == 0)
{
// Special case: If this is an INSERT statement that will insert exactly one row into the table, raise a constraint immediately instead of
// incrementing a counter. This is necessary as the VM code is being generated for will not open a statement transaction.
Debug.Assert(incr == 1);
HaltConstraint(parse, OE.Abort, "foreign key constraint failed", Vdbe.P4T.STATIC);
}
else
{
if (incr > 0 && !fkey.IsDeferred)
E.Parse_Toplevel(parse).MayAbort = true;
v.AddOp2(OP.FkCounter, fkey.IsDeferred, incr);
}
v.ResolveLabel(v, okId);
v.AddOp1(OP.Close, curId);
}