public static void DropTriggerPtr(Parse parse, Trigger trigger)
{
Context ctx = parse.Ctx;
int db = Prepare.SchemaToIndex(ctx, trigger.Schema);
Debug.Assert(db >= 0 && db < ctx.DBs.length);
Table table = TableOfTrigger(trigger);
Debug.Assert(table != null);
Debug.Assert(table.Schema == trigger.Schema || db == 1);
#if !OMIT_AUTHORIZATION
{
AUTH code = AUTH.DROP_TRIGGER;
string dbName = ctx.DBs[db].Name;
string tableName = E.SCHEMA_TABLE(db);
if (db == 1)
{
code = AUTH.DROP_TEMP_TRIGGER;
}
if (Auth.Check(parse, code, trigger.Name, table.Name, dbName) || Auth.Check(parse, AUTH.DELETE, tableName, null, dbName))
{
return;
}
}
#endif
// Generate code to destroy the database record of the trigger.
Debug.Assert(table != null);
Vdbe v = parse.GetVdbe();
if (v != null)
{
parse.BeginWriteOperation(0, db);
parse.OpenMasterTable(db);
int base_ = v.AddOpList(_dropTrigger.Length, _dropTrigger);
v.ChangeP4(base_ + 1, trigger.Name, Vdbe.P4T.TRANSIENT);
v.ChangeP4(base_ + 4, "trigger", Vdbe.P4T.STATIC);
parse.ChangeCookie(db);
v.AddOp2(Core.OP.Close, 0, 0);
v.AddOp4(Core.OP.DropTrigger, db, 0, 0, trigger.Name, 0);
if (parse.Mems < 3)
{
parse.Mems = 3;
}
}
}
public void CodeRowTriggerDirect(Parse parse, Table table, int reg, OE orconf, int ignoreJump)
{
Vdbe v = parse.GetVdbe(); // Main VM
TriggerPrg prg = GetRowTrigger(parse, this, table, orconf);
Debug.Assert(prg != null || parse.Errs != 0 || parse.Ctx.MallocFailed);
// Code the OP_Program opcode in the parent VDBE. P4 of the OP_Program is a pointer to the sub-vdbe containing the trigger program.
if (prg != null)
{
bool recursive = (Name != null && (parse.Ctx.Flags & Context.FLAG.RecTriggers) == 0);
v.AddOp3(Core.OP.Program, reg, ignoreJump, ++parse.Mems);
v.ChangeP4(-1, prg.Program, Vdbe.P4T.SUBPROGRAM);
#if DEBUG
v.Comment("Call: %s.%s", (!string.IsNullOrEmpty(p.Name) ? p.Name : "fkey"), OnErrorText(orconf));
#endif
// Set the P5 operand of the OP_Program instruction to non-zero if recursive invocation of this trigger program is disallowed. Recursive
// invocation is disallowed if (a) the sub-program is really a trigger, not a foreign key action, and (b) the flag to enable recursive triggers is clear.
v.ChangeP5((int)(recursive ? 1 : 0));
}
}
static TriggerPrg CodeRowTrigger(Parse parse, Trigger trigger, Table table, OE orconf)
{
Parse top = E.Parse_Toplevel(parse);
Context ctx = parse.Ctx; // Database handle
Debug.Assert(trigger.Name == null || table == TableOfTrigger(trigger));
Debug.Assert(top.V != null);
// Allocate the TriggerPrg and SubProgram objects. To ensure that they are freed if an error occurs, link them into the Parse.pTriggerPrg
// list of the top-level Parse object sooner rather than later.
TriggerPrg prg = new TriggerPrg(); // Value to return //: _tagalloc(ctx, sizeof(TriggerPrg), true);
if (prg == null)
{
return(null);
}
prg.Next = top.TriggerPrg;
top.TriggerPrg = prg;
Vdbe.SubProgram program; // Sub-vdbe for trigger program
prg.Program = program = new Vdbe.SubProgram(); // sqlite3DbMallocZero( db, sizeof( SubProgram ) );
if (program == null)
{
return(null);
}
top.V.LinkSubProgram(program);
prg.Trigger = trigger;
prg.Orconf = orconf;
prg.Colmasks[0] = 0xffffffff;
prg.Colmasks[1] = 0xffffffff;
// Allocate and populate a new Parse context to use for coding the trigger sub-program.
Parse subParse = new Parse(); // Parse context for sub-vdbe //: _stackalloc(ctx, sizeof(Parse), true);
if (subParse == null)
{
return(null);
}
NameContext sNC = new NameContext(); // Name context for sub-vdbe
sNC.Parse = subParse;
subParse.Ctx = ctx;
subParse.TriggerTab = table;
subParse.Toplevel = top;
subParse.AuthContext = trigger.Name;
subParse.TriggerOp = trigger.OP;
subParse.QueryLoops = parse.QueryLoops;
int endTrigger = 0; // Label to jump to if WHEN is false
Vdbe v = subParse.GetVdbe(); // Temporary VM
if (v != null)
{
#if DEBUG
v.Comment("Start: %s.%s (%s %s%s%s ON %s)",
trigger.Name, OnErrorText(orconf),
(trigger.TRtm == TRIGGER.BEFORE ? "BEFORE" : "AFTER"),
(trigger.OP == TK.UPDATE ? "UPDATE" : string.Empty),
(trigger.OP == TK.INSERT ? "INSERT" : string.Empty),
(trigger.OP == TK.DELETE ? "DELETE" : string.Empty),
table.Name);
#endif
#if !OMIT_TRACE
v.ChangeP4(-1, C._mtagprintf(ctx, "-- TRIGGER %s", trigger.Name), Vdbe.P4T.DYNAMIC);
#endif
// If one was specified, code the WHEN clause. If it evaluates to false (or NULL) the sub-vdbe is immediately halted by jumping to the
// OP_Halt inserted at the end of the program.
if (trigger.When != null)
{
Expr when = Expr.Dup(ctx, trigger.When, 0); // Duplicate of trigger WHEN expression
if (ResolveExprNames(sNC, ref when) == RC.OK && !ctx.MallocFailed)
{
endTrigger = v.MakeLabel();
subParse.IfFalse(when, endTrigger, RC_JUMPIFNULL);
}
Expr.Delete(ctx, ref when);
}
// Code the trigger program into the sub-vdbe.
CodeTriggerProgram(subParse, trigger.StepList, orconf);
// Insert an OP_Halt at the end of the sub-program.
if (endTrigger != 0)
{
v.ResolveLabel(endTrigger);
}
v.AddOp0(Core.OP.Halt);
#if DEBUG
v.Comment("End: %s.%s", trigger.Name, OnErrorText(orconf));
#endif
TransferParseError(parse, subParse);
if (!ctx.MallocFailed)
{
program.Ops.data = v.TakeOpArray(ref program.Ops.length, ref top.MaxArgs);
}
program.Mems = subParse.Mems;
program.Csrs = subParse.Tabs;
program.Token = trigger.GetHashCode();
prg.Colmasks[0] = subParse.Oldmask;
prg.Colmasks[1] = subParse.Newmask;
Vdbe.Delete(v);
}
Debug.Assert(subParse.Ainc == null && subParse.ZombieTab == null);
Debug.Assert(subParse.TriggerPrg == null && subParse.MaxArgs == 0);
C._stackfree(ctx, ref subParse);
return(prg);
}
public static void FinishTrigger(Parse parse, TriggerStep stepList, Token all)
{
Trigger trig = parse.NewTrigger; // Trigger being finished
Context ctx = parse.Ctx; // The database
Token nameToken = new Token(); // Trigger name for error reporting
parse.NewTrigger = null;
if (C._NEVER(parse.Errs != 0) || trig == null)
{
goto triggerfinish_cleanup;
}
string name = trig.Name; // Name of trigger
int db = Prepare.SchemaToIndex(parse.Ctx, trig.Schema); // Database containing the trigger
trig.StepList = stepList;
while (stepList != null)
{
stepList.Trig = trig;
stepList = stepList.Next;
}
nameToken.data = trig.Name;
nameToken.length = (uint)nameToken.data.Length;
DbFixer sFix = new DbFixer(); // Fixer object
if (sFix.FixInit(parse, db, "trigger", nameToken) && sFix.FixTriggerStep(trig.StepList))
{
goto triggerfinish_cleanup;
}
// if we are not initializing, build the sqlite_master entry
if (ctx.Init.Busy)
{
// Make an entry in the sqlite_master table
Vdbe v = parse.GetVdbe();
if (v == null)
{
goto triggerfinish_cleanup;
}
parse.BeginWriteOperation(0, db);
string z = all.data.Substring(0, (int)all.length); //: _tagstrndup(ctx, (char *)all->data, all->length);
parse.NestedParse("INSERT INTO %Q.%s VALUES('trigger',%Q,%Q,0,'CREATE TRIGGER %q')", ctx.DBs[db].Name, E.SCHEMA_TABLE(db), name, trig.Table, z);
C._tagfree(ctx, ref z);
parse.ChangeCookie(db);
v.AddParseSchemaOp(db, C._mtagprintf(ctx, "type='trigger' AND name='%q'", name));
}
if (!ctx.Init.Busy)
{
Trigger link = trig;
Debug.Assert(Btree.SchemaMutexHeld(ctx, db, null));
trig = ctx.DBs[db].Schema.TriggerHash.Insert(name, name.Length, trig);
if (trig != null)
{
ctx.MallocFailed = true;
}
else if (link.Schema == link.TabSchema)
{
int tableLength = link.Table.Length;
Table table = (Table)link.TabSchema.TableHash.Find(link.Table, tableLength, (Table)null);
Debug.Assert(table != null);
link.Next = table.Triggers;
table.Triggers = link;
}
}
triggerfinish_cleanup:
DeleteTrigger(ctx, ref trig);
Debug.Assert(parse.NewTrigger == null);
DeleteTriggerStep(ctx, ref stepList);
}
static TriggerPrg CodeRowTrigger(Parse parse, Trigger trigger, Table table, OE orconf)
{
Parse top = E.Parse_Toplevel(parse);
Context ctx = parse.Ctx; // Database handle
Debug.Assert(trigger.Name == null || table == TableOfTrigger(trigger));
Debug.Assert(top.V != null);
// Allocate the TriggerPrg and SubProgram objects. To ensure that they are freed if an error occurs, link them into the Parse.pTriggerPrg
// list of the top-level Parse object sooner rather than later.
TriggerPrg prg = new TriggerPrg(); // Value to return //: _tagalloc(ctx, sizeof(TriggerPrg), true);
if (prg == null) return null;
prg.Next = top.TriggerPrg;
top.TriggerPrg = prg;
Vdbe.SubProgram program; // Sub-vdbe for trigger program
prg.Program = program = new Vdbe.SubProgram();// sqlite3DbMallocZero( db, sizeof( SubProgram ) );
if (program == null) return null;
top.V.LinkSubProgram(program);
prg.Trigger = trigger;
prg.Orconf = orconf;
prg.Colmasks[0] = 0xffffffff;
prg.Colmasks[1] = 0xffffffff;
// Allocate and populate a new Parse context to use for coding the trigger sub-program.
Parse subParse = new Parse(); // Parse context for sub-vdbe //: _stackalloc(ctx, sizeof(Parse), true);
if (subParse == null) return null;
NameContext sNC = new NameContext(); // Name context for sub-vdbe
sNC.Parse = subParse;
subParse.Ctx = ctx;
subParse.TriggerTab = table;
subParse.Toplevel = top;
subParse.AuthContext = trigger.Name;
subParse.TriggerOp = trigger.OP;
subParse.QueryLoops = parse.QueryLoops;
int endTrigger = 0; // Label to jump to if WHEN is false
Vdbe v = subParse.GetVdbe(); // Temporary VM
if (v != null)
{
#if DEBUG
v.Comment("Start: %s.%s (%s %s%s%s ON %s)",
trigger.Name, OnErrorText(orconf),
(trigger.TRtm == TRIGGER.BEFORE ? "BEFORE" : "AFTER"),
(trigger.OP == TK.UPDATE ? "UPDATE" : string.Empty),
(trigger.OP == TK.INSERT ? "INSERT" : string.Empty),
(trigger.OP == TK.DELETE ? "DELETE" : string.Empty),
table.Name);
#endif
#if !OMIT_TRACE
v.ChangeP4(-1, C._mtagprintf(ctx, "-- TRIGGER %s", trigger.Name), Vdbe.P4T.DYNAMIC);
#endif
// If one was specified, code the WHEN clause. If it evaluates to false (or NULL) the sub-vdbe is immediately halted by jumping to the
// OP_Halt inserted at the end of the program.
if (trigger.When != null)
{
Expr when = Expr.Dup(ctx, trigger.When, 0); // Duplicate of trigger WHEN expression
if (ResolveExprNames(sNC, ref when) == RC.OK && !ctx.MallocFailed)
{
endTrigger = v.MakeLabel();
subParse.IfFalse(when, endTrigger, RC_JUMPIFNULL);
}
Expr.Delete(ctx, ref when);
}
// Code the trigger program into the sub-vdbe.
CodeTriggerProgram(subParse, trigger.StepList, orconf);
// Insert an OP_Halt at the end of the sub-program.
if (endTrigger != 0)
v.ResolveLabel(endTrigger);
v.AddOp0(Core.OP.Halt);
#if DEBUG
v.Comment("End: %s.%s", trigger.Name, OnErrorText(orconf));
#endif
TransferParseError(parse, subParse);
if (!ctx.MallocFailed)
program.Ops.data = v.TakeOpArray(ref program.Ops.length, ref top.MaxArgs);
program.Mems = subParse.Mems;
program.Csrs = subParse.Tabs;
program.Token = trigger.GetHashCode();
prg.Colmasks[0] = subParse.Oldmask;
prg.Colmasks[1] = subParse.Newmask;
Vdbe.Delete(v);
}
Debug.Assert(subParse.Ainc == null && subParse.ZombieTab == null);
Debug.Assert(subParse.TriggerPrg == null && subParse.MaxArgs == 0);
C._stackfree(ctx, ref subParse);
return prg;
}
public void CodeRowTriggerDirect(Parse parse, Table table, int reg, OE orconf, int ignoreJump)
{
Vdbe v = parse.GetVdbe(); // Main VM
TriggerPrg prg = GetRowTrigger(parse, this, table, orconf);
Debug.Assert(prg != null || parse.Errs != 0 || parse.Ctx.MallocFailed);
// Code the OP_Program opcode in the parent VDBE. P4 of the OP_Program is a pointer to the sub-vdbe containing the trigger program.
if (prg != null)
{
bool recursive = (Name != null && (parse.Ctx.Flags & Context.FLAG.RecTriggers) == 0);
v.AddOp3(Core.OP.Program, reg, ignoreJump, ++parse.Mems);
v.ChangeP4(-1, prg.Program, Vdbe.P4T.SUBPROGRAM);
#if DEBUG
v.Comment("Call: %s.%s", (!string.IsNullOrEmpty(p.Name) ? p.Name : "fkey"), OnErrorText(orconf));
#endif
// Set the P5 operand of the OP_Program instruction to non-zero if recursive invocation of this trigger program is disallowed. Recursive
// invocation is disallowed if (a) the sub-program is really a trigger, not a foreign key action, and (b) the flag to enable recursive triggers is clear.
v.ChangeP5((int)(recursive ? 1 : 0));
}
}
public static void FinishTrigger(Parse parse, TriggerStep stepList, Token all)
{
Trigger trig = parse.NewTrigger; // Trigger being finished
Context ctx = parse.Ctx; // The database
Token nameToken = new Token(); // Trigger name for error reporting
parse.NewTrigger = null;
if (C._NEVER(parse.Errs != 0) || trig == null) goto triggerfinish_cleanup;
string name = trig.Name; // Name of trigger
int db = Prepare.SchemaToIndex(parse.Ctx, trig.Schema); // Database containing the trigger
trig.StepList = stepList;
while (stepList != null)
{
stepList.Trig = trig;
stepList = stepList.Next;
}
nameToken.data = trig.Name;
nameToken.length = (uint)nameToken.data.Length;
DbFixer sFix = new DbFixer(); // Fixer object
if (sFix.FixInit(parse, db, "trigger", nameToken) && sFix.FixTriggerStep(trig.StepList))
goto triggerfinish_cleanup;
// if we are not initializing, build the sqlite_master entry
if (ctx.Init.Busy)
{
// Make an entry in the sqlite_master table
Vdbe v = parse.GetVdbe();
if (v == null) goto triggerfinish_cleanup;
parse.BeginWriteOperation(0, db);
string z = all.data.Substring(0, (int)all.length); //: _tagstrndup(ctx, (char *)all->data, all->length);
parse.NestedParse("INSERT INTO %Q.%s VALUES('trigger',%Q,%Q,0,'CREATE TRIGGER %q')", ctx.DBs[db].Name, E.SCHEMA_TABLE(db), name, trig.Table, z);
C._tagfree(ctx, ref z);
parse.ChangeCookie(db);
v.AddParseSchemaOp(db, C._mtagprintf(ctx, "type='trigger' AND name='%q'", name));
}
if (!ctx.Init.Busy)
{
Trigger link = trig;
Debug.Assert(Btree.SchemaMutexHeld(ctx, db, null));
trig = ctx.DBs[db].Schema.TriggerHash.Insert(name, name.Length, trig);
if (trig != null)
ctx.MallocFailed = true;
else if (link.Schema == link.TabSchema)
{
int tableLength = link.Table.Length;
Table table = (Table)link.TabSchema.TableHash.Find(link.Table, tableLength, (Table)null);
Debug.Assert(table != null);
link.Next = table.Triggers;
table.Triggers = link;
}
}
triggerfinish_cleanup:
DeleteTrigger(ctx, ref trig);
Debug.Assert(parse.NewTrigger == null);
DeleteTriggerStep(ctx, ref stepList);
}
public static void DropTriggerPtr(Parse parse, Trigger trigger)
{
Context ctx = parse.Ctx;
int db = Prepare.SchemaToIndex(ctx, trigger.Schema);
Debug.Assert(db >= 0 && db < ctx.DBs.length);
Table table = TableOfTrigger(trigger);
Debug.Assert(table != null);
Debug.Assert(table.Schema == trigger.Schema || db == 1);
#if !OMIT_AUTHORIZATION
{
AUTH code = AUTH.DROP_TRIGGER;
string dbName = ctx.DBs[db].Name;
string tableName = E.SCHEMA_TABLE(db);
if (db == 1) code = AUTH.DROP_TEMP_TRIGGER;
if (Auth.Check(parse, code, trigger.Name, table.Name, dbName) || Auth.Check(parse, AUTH.DELETE, tableName, null, dbName))
return;
}
#endif
// Generate code to destroy the database record of the trigger.
Debug.Assert(table != null);
Vdbe v = parse.GetVdbe();
if (v != null)
{
parse.BeginWriteOperation(0, db);
parse.OpenMasterTable(db);
int base_ = v.AddOpList(_dropTrigger.Length, _dropTrigger);
v.ChangeP4(base_ + 1, trigger.Name, Vdbe.P4T.TRANSIENT);
v.ChangeP4(base_ + 4, "trigger", Vdbe.P4T.STATIC);
parse.ChangeCookie(db);
v.AddOp2(Core.OP.Close, 0, 0);
v.AddOp4(Core.OP.DropTrigger, db, 0, 0, trigger.Name, 0);
if (parse.Mems < 3)
parse.Mems = 3;
}
}
static void FKScanChildren(Parse parse, SrcList src, Table table, Index index, FKey fkey, int[] cols, int regDataId, int incr)
{
Context ctx = parse.Ctx; // Database handle
Vdbe v = parse.GetVdbe();
Expr where_ = null; // WHERE clause to scan with
Debug.Assert(index == null || index.Table == table);
int fkIfZero = 0; // Address of OP_FkIfZero
if (incr < 0)
{
fkIfZero = v.AddOp2(OP.FkIfZero, fkey.IsDeferred, 0);
}
// Create an Expr object representing an SQL expression like:
//
// <parent-key1> = <child-key1> AND <parent-key2> = <child-key2> ...
//
// The collation sequence used for the comparison should be that of the parent key columns. The affinity of the parent key column should
// be applied to each child key value before the comparison takes place.
for (int i = 0; i < fkey.Cols.length; i++)
{
int col; // Index of column in child table
Expr left = Expr.Expr(ctx, TK.REGISTER, null); // Value from parent table row
if (left != null)
{
// Set the collation sequence and affinity of the LHS of each TK_EQ expression to the parent key column defaults.
if (index != null)
{
col = index.Columns[i];
Column colObj = table.Cols[col];
if (table.PKey == col)
{
col = -1;
}
left.TableId = regDataId + col + 1;
left.Aff = colObj.Affinity;
string collName = colObj.Coll;
if (collName == null)
{
collName = ctx.DefaultColl.Name;
}
left = Expr.AddCollateString(parse, left, collName);
}
else
{
left.TableId = regDataId;
left.Aff = AFF.INTEGER;
}
}
col = (cols != null ? cols[i] : fkey.Cols[0].From);
Debug.Assert(col >= 0);
string colName = fkey.From.Cols[col].Name; // Name of column in child table
Expr right = Expr.Expr(ctx, TK.ID, colName); // Column ref to child table
Expr eq = Expr.PExpr(parse, TK.EQ, left, right, 0); // Expression (pLeft = pRight)
where_ = Expr.And(ctx, where_, eq);
}
// If the child table is the same as the parent table, and this scan is taking place as part of a DELETE operation (operation D.2), omit the
// row being deleted from the scan by adding ($rowid != rowid) to the WHERE clause, where $rowid is the rowid of the row being deleted.
if (table == fkey.From && incr > 0)
{
Expr left = Expr.Expr(ctx, TK.REGISTER, null); // Value from parent table row
Expr right = Expr.Expr(ctx, TK.COLUMN, null); // Column ref to child table
if (left != null && right != null)
{
left.TableId = regDataId;
left.Aff = AFF.INTEGER;
right.TableId = src.Ids[0].Cursor;
right.ColumnId = -1;
}
Expr eq = Expr.PExpr(parse, TK.NE, left, right, 0); // Expression (pLeft = pRight)
where_ = Expr.And(ctx, where_, eq);
}
// Resolve the references in the WHERE clause.
NameContext nameContext; // Context used to resolve WHERE clause
nameContext = new NameContext(); // memset( &sNameContext, 0, sizeof( NameContext ) );
nameContext.SrcList = src;
nameContext.Parse = parse;
ResolveExprNames(nameContext, ref where_);
// Create VDBE to loop through the entries in src that match the WHERE clause. If the constraint is not deferred, throw an exception for
// each row found. Otherwise, for deferred constraints, increment the deferred constraint counter by incr for each row selected.
ExprList dummy = null;
WhereInfo whereInfo = Where.Begin(parse, src, where_, ref dummy, 0); // Context used by sqlite3WhereXXX()
if (incr > 0 && !fkey.IsDeferred)
{
E.Parse_Toplevel(parse).MayAbort = true;
}
v.AddOp2(OP.FkCounter, fkey.IsDeferred, incr);
if (whereInfo != null)
{
Where.End(whereInfo);
}
// Clean up the WHERE clause constructed above.
Expr.Delete(ctx, ref where_);
if (fkIfZero != 0)
{
v.JumpHere(fkIfZero);
}
}
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);
}
public static void FinishParse(Parse parse, Token end)
{
Table table = parse.NewTable; // The table being constructed
Context ctx = parse.Ctx; // The database connection
if (table == null)
{
return;
}
AddArgumentToVtab(parse);
parse.Arg.data = null;
if (table.ModuleArgs.length < 1)
{
return;
}
// If the CREATE VIRTUAL TABLE statement is being entered for the first time (in other words if the virtual table is actually being
// created now instead of just being read out of sqlite_master) then do additional initialization work and store the statement text
// in the sqlite_master table.
if (!ctx.Init.Busy)
{
// Compute the complete text of the CREATE VIRTUAL TABLE statement
if (end != null)
{
parse.NameToken.length = (uint)parse.NameToken.data.Length; //: (int)(end->data - parse->NameToken) + end->length;
}
string stmt = C._mtagprintf(ctx, "CREATE VIRTUAL TABLE %T", parse.NameToken); //.Z.Substring(0, parse.NameToken.length));
// A slot for the record has already been allocated in the SQLITE_MASTER table. We just need to update that slot with all
// the information we've collected.
//
// The VM register number pParse->regRowid holds the rowid of an entry in the sqlite_master table tht was created for this vtab
// by sqlite3StartTable().
int db = Prepare.SchemaToIndex(ctx, table.Schema);
parse.NestedParse("UPDATE %Q.%s SET type='table', name=%Q, tbl_name=%Q, rootpage=0, sql=%Q WHERE rowid=#%d",
ctx.DBs[db].Name, E.SCHEMA_TABLE(db),
table.Name, table.Name,
stmt,
parse.RegRowid
);
C._tagfree(ctx, ref stmt);
Vdbe v = parse.GetVdbe();
parse.ChangeCookie(db);
v.AddOp2(OP.Expire, 0, 0);
string where_ = C._mtagprintf(ctx, "name='%q' AND type='table'", table.Name);
v.AddParseSchemaOp(db, where_);
v.AddOp4(OP.VCreate, db, 0, 0, table.Name, (Vdbe.P4T)table.Name.Length + 1);
}
// If we are rereading the sqlite_master table create the in-memory record of the table. The xConnect() method is not called until
// the first time the virtual table is used in an SQL statement. This allows a schema that contains virtual tables to be loaded before
// the required virtual table implementations are registered.
else
{
Schema schema = table.Schema;
string name = table.Name;
int nameLength = name.Length;
Debug.Assert(Btree.SchemaMutexHeld(ctx, 0, schema));
Table oldTable = schema.TableHash.Insert(name, nameLength, table);
if (oldTable != null)
{
ctx.MallocFailed = true;
Debug.Assert(table == oldTable); // Malloc must have failed inside HashInsert()
return;
}
parse.NewTable = null;
}
}
static void FKScanChildren(Parse parse, SrcList src, Table table, Index index, FKey fkey, int[] cols, int regDataId, int incr)
{
Context ctx = parse.Ctx; // Database handle
Vdbe v = parse.GetVdbe();
Expr where_ = null; // WHERE clause to scan with
Debug.Assert(index == null || index.Table == table);
int fkIfZero = 0; // Address of OP_FkIfZero
if (incr < 0)
fkIfZero = v.AddOp2(OP.FkIfZero, fkey.IsDeferred, 0);
// Create an Expr object representing an SQL expression like:
//
// <parent-key1> = <child-key1> AND <parent-key2> = <child-key2> ...
//
// The collation sequence used for the comparison should be that of the parent key columns. The affinity of the parent key column should
// be applied to each child key value before the comparison takes place.
for (int i = 0; i < fkey.Cols.length; i++)
{
int col; // Index of column in child table
Expr left = Expr.Expr(ctx, TK.REGISTER, null); // Value from parent table row
if (left != null)
{
// Set the collation sequence and affinity of the LHS of each TK_EQ expression to the parent key column defaults.
if (index != null)
{
col = index.Columns[i];
Column colObj = table.Cols[col];
if (table.PKey == col) col = -1;
left.TableId = regDataId + col + 1;
left.Aff = colObj.Affinity;
string collName = colObj.Coll;
if (collName == null) collName = ctx.DefaultColl.Name;
left = Expr.AddCollateString(parse, left, collName);
}
else
{
left.TableId = regDataId;
left.Aff = AFF.INTEGER;
}
}
col = (cols != null ? cols[i] : fkey.Cols[0].From);
Debug.Assert(col >= 0);
string colName = fkey.From.Cols[col].Name; // Name of column in child table
Expr right = Expr.Expr(ctx, TK.ID, colName); // Column ref to child table
Expr eq = Expr.PExpr(parse, TK.EQ, left, right, 0); // Expression (pLeft = pRight)
where_ = Expr.And(ctx, where_, eq);
}
// If the child table is the same as the parent table, and this scan is taking place as part of a DELETE operation (operation D.2), omit the
// row being deleted from the scan by adding ($rowid != rowid) to the WHERE clause, where $rowid is the rowid of the row being deleted.
if (table == fkey.From && incr > 0)
{
Expr left = Expr.Expr(ctx, TK.REGISTER, null); // Value from parent table row
Expr right = Expr.Expr(ctx, TK.COLUMN, null); // Column ref to child table
if (left != null && right != null)
{
left.TableId = regDataId;
left.Aff = AFF.INTEGER;
right.TableId = src.Ids[0].Cursor;
right.ColumnIdx = -1;
}
Expr eq = Expr.PExpr(parse, TK.NE, left, right, 0); // Expression (pLeft = pRight)
where_ = Expr.And(ctx, where_, eq);
}
// Resolve the references in the WHERE clause.
NameContext nameContext; // Context used to resolve WHERE clause
nameContext = new NameContext(); // memset( &sNameContext, 0, sizeof( NameContext ) );
nameContext.SrcList = src;
nameContext.Parse = parse;
ResolveExprNames(nameContext, ref where_);
// Create VDBE to loop through the entries in src that match the WHERE clause. If the constraint is not deferred, throw an exception for
// each row found. Otherwise, for deferred constraints, increment the deferred constraint counter by incr for each row selected.
ExprList dummy = null;
WhereInfo whereInfo = Where.Begin(parse, src, where_, ref dummy, 0); // Context used by sqlite3WhereXXX()
if (incr > 0 && !fkey.IsDeferred)
E.Parse_Toplevel(parse).MayAbort = true;
v.AddOp2(OP.FkCounter, fkey.IsDeferred, incr);
if (whereInfo != null)
Where.End(whereInfo);
// Clean up the WHERE clause constructed above.
Expr.Delete(ctx, ref where_);
if (fkIfZero != 0)
v.JumpHere(fkIfZero);
}
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);
}