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deparse.c
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deparse.c
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/*-------------------------------------------------------------------------
*
* deparse.c
* Query deparser for treasuredata_fdw
*
* Portions Copyright (c) 2016, Mitsunori Komatsu
*
* IDENTIFICATION
* deparse.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "treasuredata_fdw.h"
#include "access/heapam.h"
#include "access/htup_details.h"
#include "access/sysattr.h"
#include "access/transam.h"
#include "catalog/pg_collation.h"
#include "catalog/pg_namespace.h"
#include "catalog/pg_operator.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_type.h"
#include "commands/defrem.h"
#include "nodes/nodeFuncs.h"
#include "optimizer/clauses.h"
#include "optimizer/var.h"
#include "parser/parsetree.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/syscache.h"
/*
* Global context for foreign_expr_walker's search of an expression tree.
*/
typedef struct foreign_glob_cxt
{
PlannerInfo *root; /* global planner state */
RelOptInfo *foreignrel; /* the foreign relation we are planning for */
} foreign_glob_cxt;
/*
* Local (per-tree-level) context for foreign_expr_walker's search.
* This is concerned with identifying collations used in the expression.
*/
typedef enum
{
FDW_COLLATE_NONE, /* expression is of a noncollatable type, or
* it has default collation that is not
* traceable to a foreign Var */
FDW_COLLATE_SAFE, /* collation derives from a foreign Var */
FDW_COLLATE_UNSAFE /* collation is non-default and derives from
* something other than a foreign Var */
} FDWCollateState;
typedef struct foreign_loc_cxt
{
Oid collation; /* OID of current collation, if any */
FDWCollateState state; /* state of current collation choice */
} foreign_loc_cxt;
/*
* Context for deparseExpr
*/
typedef struct deparse_expr_cxt
{
PlannerInfo *root; /* global planner state */
RelOptInfo *foreignrel; /* the foreign relation we are planning for */
QueryEngineType query_engine_type; /* Query engine type */
StringInfo buf; /* output buffer to append to */
List **params_list; /* exprs that will become remote Params */
} deparse_expr_cxt;
/*
* Functions to determine whether an expression can be evaluated safely on
* remote server.
*/
static bool foreign_expr_walker(Node *node,
foreign_glob_cxt *glob_cxt,
foreign_loc_cxt *outer_cxt);
static bool is_builtin(Oid procid);
/*
* Functions to construct string representation of a node tree.
*/
static void deparseTargetList(StringInfo buf,
PlannerInfo *root,
Index rtindex,
Relation rel,
bool is_returning,
Bitmapset *attrs_used,
List **retrieved_attrs,
QueryEngineType query_engine_type);
static void deparseReturningList(StringInfo buf, PlannerInfo *root,
Index rtindex, Relation rel,
bool trig_after_row,
List *returningList,
List **retrieved_attrs);
static void deparseColumnRef(StringInfo buf, int varno, int varattno,
PlannerInfo *root, QueryEngineType query_engine_type);
static void deparseRelation(StringInfo buf, Relation rel,
QueryEngineType query_engine_type);
static void deparseExpr(Expr *expr, deparse_expr_cxt *context);
static void deparseVar(Var *node, deparse_expr_cxt *context);
static void deparseConst(Const *node, deparse_expr_cxt *context);
static void deparseParam(Param *node, deparse_expr_cxt *context);
static void deparseArrayRef(ArrayRef *node, deparse_expr_cxt *context);
static void deparseFuncExpr(FuncExpr *node, deparse_expr_cxt *context);
static void deparseOpExpr(OpExpr *node, deparse_expr_cxt *context);
static void deparseOperatorName(StringInfo buf, Form_pg_operator opform);
static void deparseDistinctExpr(DistinctExpr *node, deparse_expr_cxt *context);
static void deparseScalarArrayOpExpr(ScalarArrayOpExpr *node,
deparse_expr_cxt *context);
static void deparseRelabelType(RelabelType *node, deparse_expr_cxt *context);
static void deparseBoolExpr(BoolExpr *node, deparse_expr_cxt *context);
static void deparseNullTest(NullTest *node, deparse_expr_cxt *context);
static void deparseArrayExpr(ArrayExpr *node, deparse_expr_cxt *context);
static void printRemoteParam(int paramindex, Oid paramtype, int32 paramtypmod,
deparse_expr_cxt *context);
static void printRemotePlaceholder(Oid paramtype, int32 paramtypmod,
deparse_expr_cxt *context);
static bool isAllowedFunction(FuncExpr *node);
static char *td_quote_identifier(const char *s, QueryEngineType query_engine_type);
static void td_deparse_string(StringInfo buf, const char *val, bool is_str, QueryEngineType query_engine_type);
static void deparseStringLiteralForQueryEngineType(StringInfo buf, const char *val, QueryEngineType query_engine_type);
/*
* Examine each qual clause in input_conds, and classify them into two groups,
* which are returned as two lists:
* - remote_conds contains expressions that can be evaluated remotely
* - local_conds contains expressions that can't be evaluated remotely
*/
void
classifyConditions(PlannerInfo *root,
RelOptInfo *baserel,
List *input_conds,
List **remote_conds,
List **local_conds)
{
ListCell *lc;
*remote_conds = NIL;
*local_conds = NIL;
foreach(lc, input_conds)
{
RestrictInfo *ri = (RestrictInfo *) lfirst(lc);
if (is_foreign_expr(root, baserel, ri->clause))
*remote_conds = lappend(*remote_conds, ri);
else
*local_conds = lappend(*local_conds, ri);
}
}
/*
* Returns true if given expr is safe to evaluate on the foreign server.
*/
bool
is_foreign_expr(PlannerInfo *root,
RelOptInfo *baserel,
Expr *expr)
{
foreign_glob_cxt glob_cxt;
foreign_loc_cxt loc_cxt;
/*
* Check that the expression consists of nodes that are safe to execute
* remotely.
*/
glob_cxt.root = root;
glob_cxt.foreignrel = baserel;
loc_cxt.collation = InvalidOid;
loc_cxt.state = FDW_COLLATE_NONE;
if (!foreign_expr_walker((Node *) expr, &glob_cxt, &loc_cxt))
return false;
/* Expressions examined here should be boolean, ie noncollatable */
Assert(loc_cxt.collation == InvalidOid);
Assert(loc_cxt.state == FDW_COLLATE_NONE);
/*
* An expression which includes any mutable functions can't be sent over
* because its result is not stable. For example, sending now() remote
* side could cause confusion from clock offsets. Future versions might
* be able to make this choice with more granularity. (We check this last
* because it requires a lot of expensive catalog lookups.)
*/
if (contain_mutable_functions((Node *) expr))
return false;
/* OK to evaluate on the remote server */
return true;
}
/*
* Check if expression is safe to execute remotely, and return true if so.
*
* In addition, *outer_cxt is updated with collation information.
*
* We must check that the expression contains only node types we can deparse,
* that all types/functions/operators are safe to send (which we approximate
* as being built-in), and that all collations used in the expression derive
* from Vars of the foreign table. Because of the latter, the logic is
* pretty close to assign_collations_walker() in parse_collate.c, though we
* can assume here that the given expression is valid.
*/
static bool
foreign_expr_walker(Node *node,
foreign_glob_cxt *glob_cxt,
foreign_loc_cxt *outer_cxt)
{
bool check_type = true;
foreign_loc_cxt inner_cxt;
Oid collation;
FDWCollateState state;
/* Need do nothing for empty subexpressions */
if (node == NULL)
return true;
/* Set up inner_cxt for possible recursion to child nodes */
inner_cxt.collation = InvalidOid;
inner_cxt.state = FDW_COLLATE_NONE;
switch (nodeTag(node))
{
case T_Var:
{
Var *var = (Var *) node;
/*
* If the Var is from the foreign table, we consider its
* collation (if any) safe to use. If it is from another
* table, we treat its collation the same way as we would a
* Param's collation, ie it's not safe for it to have a
* non-default collation.
*/
if (var->varno == glob_cxt->foreignrel->relid &&
var->varlevelsup == 0)
{
/* Var belongs to foreign table */
/*
* System columns other than ctid should not be sent to
* the remote, since we don't make any effort to ensure
* that local and remote values match (tableoid, in
* particular, almost certainly doesn't match).
*/
if (var->varattno < 0 &&
var->varattno != SelfItemPointerAttributeNumber)
return false;
/* Else check the collation */
collation = var->varcollid;
state = OidIsValid(collation) ? FDW_COLLATE_SAFE : FDW_COLLATE_NONE;
}
else
{
/* Var belongs to some other table */
collation = var->varcollid;
if (collation == InvalidOid ||
collation == DEFAULT_COLLATION_OID)
{
/*
* It's noncollatable, or it's safe to combine with a
* collatable foreign Var, so set state to NONE.
*/
state = FDW_COLLATE_NONE;
}
else
{
/*
* Do not fail right away, since the Var might appear
* in a collation-insensitive context.
*/
state = FDW_COLLATE_UNSAFE;
}
}
}
break;
case T_Const:
{
Const *c = (Const *) node;
/*
* If the constant has nondefault collation, either it's of a
* non-builtin type, or it reflects folding of a CollateExpr.
* It's unsafe to send to the remote unless it's used in a
* non-collation-sensitive context.
*/
collation = c->constcollid;
if (collation == InvalidOid ||
collation == DEFAULT_COLLATION_OID)
state = FDW_COLLATE_NONE;
else
state = FDW_COLLATE_UNSAFE;
}
break;
case T_Param:
/* This FDW doesn't support param push down */
return false;
case T_ArrayRef:
{
ArrayRef *ar = (ArrayRef *) node;
/* Assignment should not be in restrictions. */
if (ar->refassgnexpr != NULL)
return false;
/*
* Recurse to remaining subexpressions. Since the array
* subscripts must yield (noncollatable) integers, they won't
* affect the inner_cxt state.
*/
if (!foreign_expr_walker((Node *) ar->refupperindexpr,
glob_cxt, &inner_cxt))
return false;
if (!foreign_expr_walker((Node *) ar->reflowerindexpr,
glob_cxt, &inner_cxt))
return false;
if (!foreign_expr_walker((Node *) ar->refexpr,
glob_cxt, &inner_cxt))
return false;
/*
* Array subscripting should yield same collation as input,
* but for safety use same logic as for function nodes.
*/
collation = ar->refcollid;
if (collation == InvalidOid)
state = FDW_COLLATE_NONE;
else if (inner_cxt.state == FDW_COLLATE_SAFE &&
collation == inner_cxt.collation)
state = FDW_COLLATE_SAFE;
else if (collation == DEFAULT_COLLATION_OID)
state = FDW_COLLATE_NONE;
else
state = FDW_COLLATE_UNSAFE;
}
break;
case T_FuncExpr:
{
FuncExpr *fe = (FuncExpr *) node;
/*
* If function used by the expression is not built-in, it
* can't be sent to remote because it might have incompatible
* semantics on remote side.
*/
if (!is_builtin(fe->funcid))
return false;
/*
* Recurse to input subexpressions.
*/
if (!foreign_expr_walker((Node *) fe->args,
glob_cxt, &inner_cxt))
return false;
/*
* If function's input collation is not derived from a foreign
* Var, it can't be sent to remote.
*/
if (fe->inputcollid == InvalidOid)
/* OK, inputs are all noncollatable */ ;
else if (inner_cxt.state != FDW_COLLATE_SAFE ||
fe->inputcollid != inner_cxt.collation)
return false;
if (!isAllowedFunction(fe))
return false;
/*
* Detect whether node is introducing a collation not derived
* from a foreign Var. (If so, we just mark it unsafe for now
* rather than immediately returning false, since the parent
* node might not care.)
*/
collation = fe->funccollid;
if (collation == InvalidOid)
state = FDW_COLLATE_NONE;
else if (inner_cxt.state == FDW_COLLATE_SAFE &&
collation == inner_cxt.collation)
state = FDW_COLLATE_SAFE;
else if (collation == DEFAULT_COLLATION_OID)
state = FDW_COLLATE_NONE;
else
state = FDW_COLLATE_UNSAFE;
}
break;
case T_OpExpr:
case T_DistinctExpr: /* struct-equivalent to OpExpr */
{
OpExpr *oe = (OpExpr *) node;
/*
* Similarly, only built-in operators can be sent to remote.
* (If the operator is, surely its underlying function is
* too.)
*/
if (!is_builtin(oe->opno))
return false;
/*
* Recurse to input subexpressions.
*/
if (!foreign_expr_walker((Node *) oe->args,
glob_cxt, &inner_cxt))
return false;
/*
* If operator's input collation is not derived from a foreign
* Var, it can't be sent to remote.
*/
if (oe->inputcollid == InvalidOid)
/* OK, inputs are all noncollatable */ ;
else if (inner_cxt.state != FDW_COLLATE_SAFE ||
oe->inputcollid != inner_cxt.collation)
return false;
/* Result-collation handling is same as for functions */
collation = oe->opcollid;
if (collation == InvalidOid)
state = FDW_COLLATE_NONE;
else if (inner_cxt.state == FDW_COLLATE_SAFE &&
collation == inner_cxt.collation)
state = FDW_COLLATE_SAFE;
else if (collation == DEFAULT_COLLATION_OID)
state = FDW_COLLATE_NONE;
else
state = FDW_COLLATE_UNSAFE;
}
break;
case T_ScalarArrayOpExpr:
{
ScalarArrayOpExpr *oe = (ScalarArrayOpExpr *) node;
/*
* Again, only built-in operators can be sent to remote.
*/
if (!is_builtin(oe->opno))
return false;
/*
* Recurse to input subexpressions.
*/
if (!foreign_expr_walker((Node *) oe->args,
glob_cxt, &inner_cxt))
return false;
/*
* If operator's input collation is not derived from a foreign
* Var, it can't be sent to remote.
*/
if (oe->inputcollid == InvalidOid)
/* OK, inputs are all noncollatable */ ;
else if (inner_cxt.state != FDW_COLLATE_SAFE ||
oe->inputcollid != inner_cxt.collation)
return false;
{
char *opname;
Form_pg_operator form;
/* Retrieve information about the operator from system catalog. */
HeapTuple tuple = SearchSysCache1(OPEROID, ObjectIdGetDatum(oe->opno));
if (!HeapTupleIsValid(tuple))
elog(ERROR, "cache lookup failed for operator %u", oe->opno);
form = (Form_pg_operator) GETSTRUCT(tuple);
opname = NameStr(form->oprname);
/*
* x IN (a, b, c) => opname:'=', node->useOr:true (Available on TD)
* x NOT IN (a, b, c) => opname:'<>', node->useOr:false (Available on TD)
* x = ANY('{a,b,c}') => opname:'=', node->useOr:true (Can be converted to `IN`)
*
* Other than the above are not supported
*/
if (!(strcmp(opname, "=") == 0 && oe->useOr) && !(strcmp(opname, "<>") == 0 && !oe->useOr))
{
elog(DEBUG1, "Unsupported operator combination in scalar array. opname=[%s], node->useOr=%d", opname, oe->useOr);
ReleaseSysCache(tuple);
return false;
}
ReleaseSysCache(tuple);
}
/* Output is always boolean and so noncollatable. */
collation = InvalidOid;
state = FDW_COLLATE_NONE;
}
break;
case T_RelabelType:
{
RelabelType *r = (RelabelType *) node;
/*
* Recurse to input subexpression.
*/
if (!foreign_expr_walker((Node *) r->arg,
glob_cxt, &inner_cxt))
return false;
/*
* RelabelType must not introduce a collation not derived from
* an input foreign Var (same logic as for a real function).
*/
collation = r->resultcollid;
if (collation == InvalidOid)
state = FDW_COLLATE_NONE;
else if (inner_cxt.state == FDW_COLLATE_SAFE &&
collation == inner_cxt.collation)
state = FDW_COLLATE_SAFE;
else if (collation == DEFAULT_COLLATION_OID)
state = FDW_COLLATE_NONE;
else
state = FDW_COLLATE_UNSAFE;
}
break;
case T_BoolExpr:
{
BoolExpr *b = (BoolExpr *) node;
/*
* Recurse to input subexpressions.
*/
if (!foreign_expr_walker((Node *) b->args,
glob_cxt, &inner_cxt))
return false;
/* Output is always boolean and so noncollatable. */
collation = InvalidOid;
state = FDW_COLLATE_NONE;
}
break;
case T_NullTest:
{
NullTest *nt = (NullTest *) node;
/*
* Recurse to input subexpressions.
*/
if (!foreign_expr_walker((Node *) nt->arg,
glob_cxt, &inner_cxt))
return false;
/* Output is always boolean and so noncollatable. */
collation = InvalidOid;
state = FDW_COLLATE_NONE;
}
break;
case T_ArrayExpr:
{
ArrayExpr *a = (ArrayExpr *) node;
/*
* Recurse to input subexpressions.
*/
if (!foreign_expr_walker((Node *) a->elements,
glob_cxt, &inner_cxt))
return false;
/*
* ArrayExpr must not introduce a collation not derived from
* an input foreign Var (same logic as for a function).
*/
collation = a->array_collid;
if (collation == InvalidOid)
state = FDW_COLLATE_NONE;
else if (inner_cxt.state == FDW_COLLATE_SAFE &&
collation == inner_cxt.collation)
state = FDW_COLLATE_SAFE;
else if (collation == DEFAULT_COLLATION_OID)
state = FDW_COLLATE_NONE;
else
state = FDW_COLLATE_UNSAFE;
}
break;
case T_List:
{
List *l = (List *) node;
ListCell *lc;
/*
* Recurse to component subexpressions.
*/
foreach(lc, l)
{
if (!foreign_expr_walker((Node *) lfirst(lc),
glob_cxt, &inner_cxt))
return false;
}
/*
* When processing a list, collation state just bubbles up
* from the list elements.
*/
collation = inner_cxt.collation;
state = inner_cxt.state;
/* Don't apply exprType() to the list. */
check_type = false;
}
break;
default:
/*
* If it's anything else, assume it's unsafe. This list can be
* expanded later, but don't forget to add deparse support below.
*/
return false;
}
/*
* If result type of given expression is not built-in, it can't be sent to
* remote because it might have incompatible semantics on remote side.
*/
if (check_type && !is_builtin(exprType(node)))
return false;
/*
* Now, merge my collation information into my parent's state.
*/
if (state > outer_cxt->state)
{
/* Override previous parent state */
outer_cxt->collation = collation;
outer_cxt->state = state;
}
else if (state == outer_cxt->state)
{
/* Merge, or detect error if there's a collation conflict */
switch (state)
{
case FDW_COLLATE_NONE:
/* Nothing + nothing is still nothing */
break;
case FDW_COLLATE_SAFE:
if (collation != outer_cxt->collation)
{
/*
* Non-default collation always beats default.
*/
if (outer_cxt->collation == DEFAULT_COLLATION_OID)
{
/* Override previous parent state */
outer_cxt->collation = collation;
}
else if (collation != DEFAULT_COLLATION_OID)
{
/*
* Conflict; show state as indeterminate. We don't
* want to "return false" right away, since parent
* node might not care about collation.
*/
outer_cxt->state = FDW_COLLATE_UNSAFE;
}
}
break;
case FDW_COLLATE_UNSAFE:
/* We're still conflicted ... */
break;
}
}
/* It looks OK */
return true;
}
/*
* Return true if given object is one of PostgreSQL's built-in objects.
*
* We use FirstBootstrapObjectId as the cutoff, so that we only consider
* objects with hand-assigned OIDs to be "built in", not for instance any
* function or type defined in the information_schema.
*
* Our constraints for dealing with types are tighter than they are for
* functions or operators: we want to accept only types that are in pg_catalog,
* else format_type might incorrectly fail to schema-qualify their names.
* (This could be fixed with some changes to format_type, but for now there's
* no need.) Thus we must exclude information_schema types.
*
* XXX there is a problem with this, which is that the set of built-in
* objects expands over time. Something that is built-in to us might not
* be known to the remote server, if it's of an older version. But keeping
* track of that would be a huge exercise.
*/
static bool
is_builtin(Oid oid)
{
return (oid < FirstBootstrapObjectId);
}
/*
* Construct a simple SELECT statement that retrieves desired columns
* of the specified foreign table, and append it to "buf". The output
* contains just "SELECT ... FROM tablename".
*
* We also create an integer List of the columns being retrieved, which is
* returned to *retrieved_attrs.
*/
void
deparseSelectSql(StringInfo buf,
PlannerInfo *root,
RelOptInfo *baserel,
Bitmapset *attrs_used,
List **retrieved_attrs,
QueryEngineType query_engine_type)
{
RangeTblEntry *rte = planner_rt_fetch(baserel->relid, root);
Relation rel;
/*
* Core code already has some lock on each rel being planned, so we can
* use NoLock here.
*/
rel = heap_open(rte->relid, NoLock);
/*
* Construct SELECT list
*/
appendStringInfoString(buf, "SELECT ");
deparseTargetList(buf, root, baserel->relid, rel, false, attrs_used,
retrieved_attrs, query_engine_type);
/*
* Construct FROM clause
*/
appendStringInfoString(buf, " FROM ");
deparseRelation(buf, rel, query_engine_type);
heap_close(rel, NoLock);
}
/*
* Emit a target list that retrieves the columns specified in attrs_used.
* This is used for both SELECT and RETURNING targetlists; the is_returning
* parameter is true only for a RETURNING targetlist.
*
* The tlist text is appended to buf, and we also create an integer List
* of the columns being retrieved, which is returned to *retrieved_attrs.
*/
static void
deparseTargetList(StringInfo buf,
PlannerInfo *root,
Index rtindex,
Relation rel,
bool is_returning,
Bitmapset *attrs_used,
List **retrieved_attrs,
QueryEngineType query_engine_type)
{
TupleDesc tupdesc = RelationGetDescr(rel);
bool have_wholerow;
bool first;
int i;
*retrieved_attrs = NIL;
/* If there's a whole-row reference, we'll need all the columns. */
have_wholerow = bms_is_member(0 - FirstLowInvalidHeapAttributeNumber,
attrs_used);
first = true;
for (i = 1; i <= tupdesc->natts; i++)
{
Form_pg_attribute attr = TupleDescAttr(tupdesc, i - 1);
/* Ignore dropped attributes. */
if (attr->attisdropped)
continue;
if (have_wholerow ||
bms_is_member(i - FirstLowInvalidHeapAttributeNumber,
attrs_used))
{
if (!first)
appendStringInfoString(buf, ", ");
else if (is_returning)
appendStringInfoString(buf, " RETURNING ");
first = false;
deparseColumnRef(buf, rtindex, i, root, query_engine_type);
*retrieved_attrs = lappend_int(*retrieved_attrs, i);
}
}
/*
* Add ctid if needed. We currently don't support retrieving any other
* system columns.
*/
if (bms_is_member(SelfItemPointerAttributeNumber - FirstLowInvalidHeapAttributeNumber,
attrs_used))
{
if (!first)
appendStringInfoString(buf, ", ");
else if (is_returning)
appendStringInfoString(buf, " RETURNING ");
first = false;
appendStringInfoString(buf, "ctid");
*retrieved_attrs = lappend_int(*retrieved_attrs,
SelfItemPointerAttributeNumber);
}
/* Don't generate bad syntax if no undropped columns */
if (first && !is_returning)
appendStringInfoString(buf, "CAST(NULL AS TINYINT)");
}
/*
* Deparse WHERE clauses in given list of RestrictInfos and append them to buf.
*
* baserel is the foreign table we're planning for.
*
* If no WHERE clause already exists in the buffer, is_first should be true.
*
* If params is not NULL, it receives a list of Params and other-relation Vars
* used in the clauses; these values must be transmitted to the remote server
* as parameter values.
*
* If params is NULL, we're generating the query for EXPLAIN purposes,
* so Params and other-relation Vars should be replaced by dummy values.
*/
void
appendWhereClause(StringInfo buf,
PlannerInfo *root,
RelOptInfo *baserel,
List *exprs,
bool is_first,
List **params,
QueryEngineType query_engine_type)
{
deparse_expr_cxt context;
ListCell *lc;
if (params)
*params = NIL; /* initialize result list to empty */
/* Set up context struct for recursion */
context.root = root;
context.foreignrel = baserel;
context.query_engine_type = query_engine_type;
context.buf = buf;
context.params_list = params;
foreach(lc, exprs)
{
RestrictInfo *ri = (RestrictInfo *) lfirst(lc);
/* Connect expressions with "AND" and parenthesize each condition. */
if (is_first)
appendStringInfoString(buf, " WHERE ");
else
appendStringInfoString(buf, " AND ");
appendStringInfoChar(buf, '(');
deparseExpr(ri->clause, &context);
appendStringInfoChar(buf, ')');
is_first = false;
}
}
/*
* deparse remote INSERT statement
*
* The statement text is appended to buf, and we also create an integer List
* of the columns being retrieved by RETURNING (if any), which is returned
* to *retrieved_attrs.
*/
void
deparseInsertSql(StringInfo buf, PlannerInfo *root,
Index rtindex, Relation rel,
List *targetAttrs, bool doNothing,
List *returningList, List **retrieved_attrs)
{
AttrNumber pindex;
bool first;
ListCell *lc;
appendStringInfoString(buf, "INSERT INTO ");
/* TODO: Support Hive */
deparseRelation(buf, rel, QUERY_ENGINE_PRESTO);
if (targetAttrs)
{
appendStringInfoChar(buf, '(');
first = true;
foreach(lc, targetAttrs)
{
int attnum = lfirst_int(lc);
if (!first)
appendStringInfoString(buf, ", ");
first = false;
/* TODO: Support Hive */
deparseColumnRef(buf, rtindex, attnum, root, QUERY_ENGINE_PRESTO);
}
appendStringInfoString(buf, ") VALUES (");
pindex = 1;
first = true;
foreach(lc, targetAttrs)
{
if (!first)
appendStringInfoString(buf, ", ");
first = false;
appendStringInfo(buf, "$%d", pindex);
pindex++;
}
appendStringInfoChar(buf, ')');
}
else
appendStringInfoString(buf, " DEFAULT VALUES");
if (doNothing)
appendStringInfoString(buf, " ON CONFLICT DO NOTHING");
deparseReturningList(buf, root, rtindex, rel,
rel->trigdesc && rel->trigdesc->trig_insert_after_row,
returningList, retrieved_attrs);
}
/*
* deparse remote UPDATE statement
*
* The statement text is appended to buf, and we also create an integer List
* of the columns being retrieved by RETURNING (if any), which is returned
* to *retrieved_attrs.
*/
void
deparseUpdateSql(StringInfo buf, PlannerInfo *root,
Index rtindex, Relation rel,
List *targetAttrs, List *returningList,
List **retrieved_attrs)
{
AttrNumber pindex;
bool first;
ListCell *lc;
appendStringInfoString(buf, "UPDATE ");
/* TODO: Support Hive */
deparseRelation(buf, rel, QUERY_ENGINE_PRESTO);
appendStringInfoString(buf, " SET ");
pindex = 2; /* ctid is always the first param */
first = true;
foreach(lc, targetAttrs)
{
int attnum = lfirst_int(lc);
if (!first)
appendStringInfoString(buf, ", ");
first = false;
/* TODO: Support Hive */
deparseColumnRef(buf, rtindex, attnum, root, QUERY_ENGINE_PRESTO);
appendStringInfo(buf, " = $%d", pindex);
pindex++;
}
appendStringInfoString(buf, " WHERE ctid = $1");
deparseReturningList(buf, root, rtindex, rel,
rel->trigdesc && rel->trigdesc->trig_update_after_row,
returningList, retrieved_attrs);
}
/*
* deparse remote DELETE statement
*
* The statement text is appended to buf, and we also create an integer List
* of the columns being retrieved by RETURNING (if any), which is returned
* to *retrieved_attrs.
*/
void
deparseDeleteSql(StringInfo buf, PlannerInfo *root,
Index rtindex, Relation rel,
List *returningList,
List **retrieved_attrs)
{
appendStringInfoString(buf, "DELETE FROM ");
/* TODO: Support Hive */
deparseRelation(buf, rel, QUERY_ENGINE_PRESTO);
appendStringInfoString(buf, " WHERE ctid = $1");
deparseReturningList(buf, root, rtindex, rel,
rel->trigdesc && rel->trigdesc->trig_delete_after_row,
returningList, retrieved_attrs);