Field, date truncate method

Makefile

@@ -1,4 +1,9 @@
+.PHONY: run bench-select test
+
 run:
-	go run ./cmd -o ./example/db ./example/schema.sql
+	go run ./cmd -o ./playground/db ./playground/schema.sql
 bench-select:
 	go test ./example -bench BenchmarkSelect -memprofile memprofile.out -cpuprofile profile.out
+
+test:
+	go test ./playground

cmd/generate.go

@@ -95,6 +95,8 @@ func writeColFile(tblName string, cols []*Column, outDir string, caser cases.Cas
 	sb.WriteString(fmt.Sprintf("package %s\n\n", filepath.Base(outDir)))
 	sb.WriteString(fmt.Sprintf("import %q\n\n", "code.patial.tech/go/pgm"))
 	sb.WriteString("const (")
+	sb.WriteString("\n // All fields in table " + tblName)
+	sb.WriteString(fmt.Sprintf("\n All pgm.Field = %q", tblName+".*"))
 	var name string
 	for _, c := range cols {
 		name = strings.ReplaceAll(c.Name, "_", " ")

pgm.go

@@ -1,155 +1,103 @@
-// Patial Tech.
-// Author, Ankit Patial
+// pgm
+//
+// A simple PG string query builder
+//
+// Author: Ankit Patial
 
 package pgm
 
 import (
-	"strings"
+	"context"
+	"errors"
+	"log/slog"
+	"sync/atomic"
 	"time"
 
+	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgtype"
+	"github.com/jackc/pgx/v5/pgxpool"
 )
 
-// Table in database
-type Table struct {
-	Name       string
-	PK         []string
-	FieldCount uint16
-	debug      bool
+var (
+	poolPGX              atomic.Pointer[pgxpool.Pool]
+	ErrConnStringMissing = errors.New("connection string is empty")
+)
+
+// Errors
+var (
+	ErrInitTX   = errors.New("failed to init db.tx")
+	ErrCommitTX = errors.New("failed to commit db.tx")
+	ErrNoRows   = errors.New("no data found")
+)
+
+type Config struct {
+	ConnString      string
+	MaxConns        int32
+	MinConns        int32
+	MaxConnLifetime time.Duration
+	MaxConnIdleTime time.Duration
 }
 
-// Debug when set true will print generated query string in stdout
-func (t Table) Debug() Clause {
-	t.debug = true
-	return t
+// InitPool will create new pgxpool.Pool and will keep it for its working
+func InitPool(conf Config) {
+	if conf.ConnString == "" {
+		panic(ErrConnStringMissing)
+	}
+
+	cfg, err := pgxpool.ParseConfig(conf.ConnString)
+	if err != nil {
+		panic(err)
+	}
+
+	if conf.MaxConns > 0 {
+		cfg.MaxConns = conf.MaxConns // 100
+	}
+
+	if conf.MinConns > 0 {
+		cfg.MinConns = conf.MaxConns // 5
+	}
+
+	if conf.MaxConnLifetime > 0 {
+		cfg.MaxConnLifetime = conf.MaxConnLifetime // time.Minute * 10
+	}
+
+	if conf.MaxConnIdleTime > 0 {
+		cfg.MaxConnIdleTime = conf.MaxConnIdleTime // time.Minute * 5
+	}
+
+	p, err := pgxpool.NewWithConfig(context.Background(), cfg)
+	if err != nil {
+		panic(err)
+	}
+
+	if err = p.Ping(context.Background()); err != nil {
+		panic(err)
+	}
+
+	poolPGX.Store(p)
 }
 
-//
-//  Field ==>
-//
-
-// Field related to a table
-type Field string
-
-func (f Field) Name() string {
-	return strings.Split(string(f), ".")[1]
+// GetPool instance
+func GetPool() *pgxpool.Pool {
+	return poolPGX.Load()
 }
 
-func (f Field) String() string {
-	return string(f)
+// BeginTx begins a pgx poll transaction
+func BeginTx(ctx context.Context) (pgx.Tx, error) {
+	tx, err := poolPGX.Load().Begin(ctx)
+	if err != nil {
+		slog.Error(err.Error())
+		return nil, errors.New("failed to open db tx")
+	}
+
+	return tx, err
 }
 
-// Count fn wrapping of field
-func (f Field) Count() Field {
-	return Field("COUNT(" + f.String() + ")")
+// IsNotFound error check
+func IsNotFound(err error) bool {
+	return errors.Is(err, pgx.ErrNoRows)
 }
 
-// Avg fn wrapping of field
-func (f Field) Avg() Field {
-	return Field("AVG(" + f.String() + ")")
-}
-
-func (f Field) Sum() Field {
-	return Field("SUM(" + f.String() + ")")
-}
-
-func (f Field) Max() Field {
-	return Field("MAX(" + f.String() + ")")
-}
-
-func (f Field) Min() Field {
-	return Field("Min(" + f.String() + ")")
-}
-
-func (f Field) Lower() Field {
-	return Field("LOWER(" + f.String() + ")")
-}
-
-func (f Field) Upper() Field {
-	return Field("UPPER(" + f.String() + ")")
-}
-
-func (f Field) Trim() Field {
-	return Field("TRIM(" + f.String() + ")")
-}
-
-func (f Field) IsNull() Conditioner {
-	col := f.String()
-	return &Cond{Field: col, op: " IS NULL", len: len(col) + 8}
-}
-
-func (f Field) IsNotNull() Conditioner {
-	col := f.String()
-	return &Cond{Field: col, op: " IS NOT NULL", len: len(col) + 12}
-}
-
-// Eq is equal
-func (f Field) Eq(val any) Conditioner {
-	col := f.String()
-	return &Cond{Field: col, Val: val, op: " = $", len: len(col) + 5}
-}
-
-// EqualFold will user LOWER() for comparision
-func (f Field) EqFold(val any) Conditioner {
-	col := f.String()
-	return &Cond{Field: "LOWER(" + col + ")", Val: val, op: " = LOWER($", action: CondActionNeedToClose, len: len(col) + 5}
-}
-
-func (f Field) NEq(val any) Conditioner {
-	col := f.String()
-	return &Cond{Field: col, Val: val, op: " != $", len: len(col) + 5}
-}
-
-func (f Field) Gt(val any) Conditioner {
-	col := f.String()
-	return &Cond{Field: col, Val: val, op: " > $", len: len(col) + 5}
-}
-
-func (f Field) Lt(val any) Conditioner {
-	col := f.String()
-	return &Cond{Field: col, Val: val, op: " < $", len: len(col) + 5}
-}
-
-func (f Field) Gte(val any) Conditioner {
-	col := f.String()
-	return &Cond{Field: col, Val: val, op: " >= $", len: len(col) + 5}
-}
-
-func (f Field) Lte(val any) Conditioner {
-	col := f.String()
-	return &Cond{Field: col, Val: val, op: " <= $", len: len(col) + 5}
-}
-
-func (f Field) Like(val string) Conditioner {
-	col := f.String()
-	return &Cond{Field: col, Val: val, op: " LIKE $", len: len(f.String()) + 5}
-}
-
-func (f Field) LikeFold(val string) Conditioner {
-	col := f.String()
-	return &Cond{Field: "LOWER(" + col + ")", Val: val, op: " LIKE LOWER($", action: CondActionNeedToClose, len: len(col) + 5}
-}
-
-// ILIKE is case-insensitive
-func (f Field) ILike(val string) Conditioner {
-	col := f.String()
-	return &Cond{Field: col, Val: val, op: " ILIKE $", len: len(col) + 5}
-}
-
-func (f Field) NotIn(val ...any) Conditioner {
-	col := f.String()
-	return &Cond{Field: col, Val: val, op: " NOT IN($", action: CondActionNeedToClose, len: len(col) + 5}
-}
-
-func (f Field) NotInSubQuery(qry WhereClause) Conditioner {
-	col := f.String()
-	return &Cond{Field: col, Val: qry, op: " NOT IN($)", action: CondActionSubQuery}
-}
-
-//
-//  Helper func ==>
-//
-
 // PgTime as in UTC
 func PgTime(t time.Time) pgtype.Timestamptz {
 	return pgtype.Timestamptz{Time: t, Valid: true}
@@ -158,15 +106,3 @@ func PgTime(t time.Time) pgtype.Timestamptz {
 func PgTimeNow() pgtype.Timestamptz {
 	return pgtype.Timestamptz{Time: time.Now(), Valid: true}
 }
-
-func ConcatWs(sep string, fields ...Field) Field {
-	return Field("concat_ws('" + sep + "'," + joinFileds(fields) + ")")
-}
-
-func StringAgg(exp, sep string) Field {
-	return Field("string_agg(" + exp + ",'" + sep + "')")
-}
-
-func StringAggCast(exp, sep string) Field {
-	return Field("string_agg(cast(" + exp + " as varchar),'" + sep + "')")
-}

pgm_field.go

@@ -0,0 +1,238 @@
+package pgm
+
+import "strings"
+
+// Field related to a table
+type Field string
+
+func (f Field) Name() string {
+	return strings.Split(string(f), ".")[1]
+}
+
+func (f Field) String() string {
+	return string(f)
+}
+
+// Count function wrapped field
+func (f Field) Count() Field {
+	return Field("COUNT(" + f.String() + ")")
+}
+
+// StringEscape will wrap field with:
+//
+// COALESCE(field, ”)
+func (f Field) StringEscape() Field {
+	return Field("COALESCE(" + f.String() + ", '')")
+}
+
+// NumberEscape will wrap field with:
+//
+// COALESCE(field, 0)
+func (f Field) NumberEscape() Field {
+	return Field("COALESCE(" + f.String() + ", 0)")
+}
+
+// BooleanEscape will wrap field with:
+//
+// COALESCE(field, FALSE)
+func (f Field) BooleanEscape() Field {
+	return Field("COALESCE(" + f.String() + ", FALSE)")
+}
+
+// Avg function wrapped field
+func (f Field) Avg() Field {
+	return Field("AVG(" + f.String() + ")")
+}
+
+// Sum function wrapped field
+func (f Field) Sum() Field {
+	return Field("SUM(" + f.String() + ")")
+}
+
+// Max function wrapped field
+func (f Field) Max() Field {
+	return Field("MAX(" + f.String() + ")")
+}
+
+// Min function wrapped field
+func (f Field) Min() Field {
+	return Field("Min(" + f.String() + ")")
+}
+
+// Lower function wrapped field
+func (f Field) Lower() Field {
+	return Field("LOWER(" + f.String() + ")")
+}
+
+// Upper function wrapped field
+func (f Field) Upper() Field {
+	return Field("UPPER(" + f.String() + ")")
+}
+
+// Trim function wrapped field
+func (f Field) Trim() Field {
+	return Field("TRIM(" + f.String() + ")")
+}
+
+// Asc suffixed field, supposed to be used with order by
+func (f Field) Asc() Field {
+	return Field(f.String() + " ASC")
+}
+
+// Desc suffixed field, supposed to be used with order by
+func (f Field) Desc() Field {
+	return Field(f.String() + " DESC")
+}
+
+func (f Field) RowNumber(as string) Field {
+	return rowNumber(&f, nil, true, as)
+}
+
+func (f Field) RowNumberDesc(as string) Field {
+	return rowNumber(&f, nil, true, as)
+}
+
+// RowNumberPartionBy in ascending order
+func (f Field) RowNumberPartionBy(partition Field, as string) Field {
+	return rowNumber(&f, &partition, true, as)
+}
+
+func (f Field) RowNumberDescPartionBy(partition Field, as string) Field {
+	return rowNumber(&f, &partition, false, as)
+}
+
+func rowNumber(f, partition *Field, isAsc bool, as string) Field {
+	var orderBy string
+	if isAsc {
+		orderBy = " ASC"
+	} else {
+		orderBy = " DESC"
+	}
+
+	if as == "" {
+		as = "row_number"
+	}
+
+	col := f.String()
+	if partition != nil {
+		return Field("ROW_NUMBER() OVER (PARTITION BY " + partition.String() + " ORDER BY " + col + orderBy + ") AS " + as)
+	}
+
+	return Field("ROW_NUMBER() OVER (ORDER BY " + col + orderBy + ") AS " + as)
+}
+
+func (f Field) IsNull() Conditioner {
+	col := f.String()
+	return &Cond{Field: col, op: " IS NULL", len: len(col) + 8}
+}
+
+func (f Field) IsNotNull() Conditioner {
+	col := f.String()
+	return &Cond{Field: col, op: " IS NOT NULL", len: len(col) + 12}
+}
+
+// DateTrunc will truncate date or timestamp to specified level of precision
+//
+// Level values:
+//   - microseconds, milliseconds, second, minute, hour
+//   - day, week (Monday start), month, quarter, year
+//   - decade, century, millennium
+func (f Field) DateTrunc(level, as string) Field {
+	return Field("DATE_TRUNC('" + level + "', " + f.String() + ") AS " + as)
+}
+
+// EqualFold will use LOWER(column_name) = LOWER(val) for comparision
+func (f Field) EqFold(val string) Conditioner {
+	col := f.String()
+	return &Cond{Field: "LOWER(" + col + ")", Val: val, op: " = LOWER($", action: CondActionNeedToClose, len: len(col) + 5}
+}
+
+// Eq is equal
+func (f Field) Eq(val any) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: val, op: " = $", len: len(col) + 5}
+}
+
+func (f Field) NotEq(val any) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: val, op: " != $", len: len(col) + 5}
+}
+
+func (f Field) Gt(val any) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: val, op: " > $", len: len(col) + 5}
+}
+
+func (f Field) Lt(val any) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: val, op: " < $", len: len(col) + 5}
+}
+
+func (f Field) Gte(val any) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: val, op: " >= $", len: len(col) + 5}
+}
+
+func (f Field) Lte(val any) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: val, op: " <= $", len: len(col) + 5}
+}
+
+func (f Field) Like(val string) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: val, op: " LIKE $", len: len(f.String()) + 5}
+}
+
+func (f Field) LikeFold(val string) Conditioner {
+	col := f.String()
+	return &Cond{Field: "LOWER(" + col + ")", Val: val, op: " LIKE LOWER($", action: CondActionNeedToClose, len: len(col) + 5}
+}
+
+// ILIKE is case-insensitive
+func (f Field) ILike(val string) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: val, op: " ILIKE $", len: len(col) + 5}
+}
+
+func (f Field) Any(val ...any) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: val, op: " = ANY($", action: CondActionNeedToClose, len: len(col) + 5}
+}
+
+func (f Field) NotAny(val ...any) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: val, op: " != ANY($", action: CondActionNeedToClose, len: len(col) + 5}
+}
+
+// NotInSubQuery using ANY
+func (f Field) NotInSubQuery(qry WhereClause) Conditioner {
+	col := f.String()
+	return &Cond{Field: col, Val: qry, op: " != ANY($)", action: CondActionSubQuery}
+}
+
+func ConcatWs(sep string, fields ...Field) Field {
+	return Field("concat_ws('" + sep + "'," + joinFileds(fields) + ")")
+}
+
+func StringAgg(exp, sep string) Field {
+	return Field("string_agg(" + exp + ",'" + sep + "')")
+}
+
+func StringAggCast(exp, sep string) Field {
+	return Field("string_agg(cast(" + exp + " as varchar),'" + sep + "')")
+}
+
+func joinFileds(fields []Field) string {
+	sb := getSB()
+	defer putSB(sb)
+	for i, f := range fields {
+		if i == 0 {
+			sb.WriteString(f.String())
+		} else {
+			sb.WriteString(", ")
+			sb.WriteString(f.String())
+		}
+	}
+
+	return sb.String()
+}

pgm_table.go

@@ -0,0 +1,71 @@
+package pgm
+
+// Table in database
+type Table struct {
+	Name         string
+	DerivedTable Query
+	PK           []string
+	FieldCount   uint16
+	debug        bool
+}
+
+// Debug when set true will print generated query string in stdout
+func (t *Table) Debug() Clause {
+	t.debug = true
+	return t
+}
+
+func (t *Table) Field(f string) Field {
+	return Field(t.Name + "." + f)
+}
+
+// Insert table statement
+func (t *Table) Insert() InsertClause {
+	qb := &insertQry{
+		debug:  t.debug,
+		table:  t.Name,
+		fields: make([]string, 0, t.FieldCount),
+		vals:   make([]string, 0, t.FieldCount),
+		args:   make([]any, 0, t.FieldCount),
+	}
+	return qb
+}
+
+// Select table statement
+func (t *Table) Select(field ...Field) SelectClause {
+	qb := &selectQry{
+		debug:  t.debug,
+		fields: field,
+	}
+
+	if t.DerivedTable != nil {
+		tName, args := t.DerivedTable.Build(true)
+		qb.table = "(" + tName + ") AS " + t.Name
+		qb.args = args
+	} else {
+		qb.table = t.Name
+	}
+
+	return qb
+}
+
+// Update table statement
+func (t *Table) Update() UpdateClause {
+	qb := &updateQry{
+		debug: t.debug,
+		table: t.Name,
+		cols:  make([]string, 0, t.FieldCount),
+		args:  make([]any, 0, t.FieldCount),
+	}
+	return qb
+}
+
+// Detlete table statement
+func (t *Table) Delete() DeleteCluase {
+	qb := &deleteQry{
+		debug: t.debug,
+		table: t.Name,
+	}
+
+	return qb
+}

playground/db/branchuser/branch_users.go

@@ -1,10 +1,12 @@
-// Code generated by db-gen. DO NOT EDIT.
+// Code generated by code.patial.tech/go/pgm/cmd DO NOT EDIT.
 
 package branchuser
 
 import "code.patial.tech/go/pgm"
 
 const (
+	// All fields in table branch_users
+	All pgm.Field = "branch_users.*"
 	// BranchID field has db type "bigint NOT NULL"
 	BranchID pgm.Field = "branch_users.branch_id"
 	// UserID field has db type "bigint NOT NULL"

playground/db/comment/comments.go

@@ -1,10 +1,12 @@
-// Code generated by db-gen. DO NOT EDIT.
+// Code generated by code.patial.tech/go/pgm/cmd DO NOT EDIT.
 
 package comment
 
 import "code.patial.tech/go/pgm"
 
 const (
+	// All fields in table comments
+	All pgm.Field = "comments.*"
 	// ID field has db type "integer NOT NULL"
 	ID pgm.Field = "comments.id"
 	// PostID field has db type "integer NOT NULL"

playground/db/derived.go

@@ -0,0 +1,11 @@
+package db
+
+import "code.patial.tech/go/pgm"
+
+func DerivedTable(tblName string, fromQry pgm.Query) pgm.Table {
+	t := pgm.Table{
+		Name:         tblName,
+		DerivedTable: fromQry,
+	}
+	return t
+}

playground/db/employee/employees.go

@@ -1,10 +1,12 @@
-// Code generated by db-gen. DO NOT EDIT.
+// Code generated by code.patial.tech/go/pgm/cmd DO NOT EDIT.
 
 package employee
 
 import "code.patial.tech/go/pgm"
 
 const (
+	// All fields in table employees
+	All pgm.Field = "employees.*"
 	// ID field has db type "integer NOT NULL"
 	ID pgm.Field = "employees.id"
 	// Name field has db type "var NOT NULL"

playground/db/post/posts.go

@@ -1,10 +1,12 @@
-// Code generated by db-gen. DO NOT EDIT.
+// Code generated by code.patial.tech/go/pgm/cmd DO NOT EDIT.
 
 package post
 
 import "code.patial.tech/go/pgm"
 
 const (
+	// All fields in table posts
+	All pgm.Field = "posts.*"
 	// ID field has db type "integer NOT NULL"
 	ID pgm.Field = "posts.id"
 	// UserID field has db type "integer NOT NULL"

playground/db/schema.go

@@ -1,5 +1,4 @@
-// Code generated by code.patial.tech/go/pgm/cmd
-// DO NOT EDIT.
+// Code generated by code.patial.tech/go/pgm/cmd DO NOT EDIT.
 
 package db
 

playground/db/user/users.go

@@ -1,10 +1,12 @@
-// Code generated by db-gen. DO NOT EDIT.
+// Code generated by code.patial.tech/go/pgm/cmd DO NOT EDIT.
 
 package user
 
 import "code.patial.tech/go/pgm"
 
 const (
+	// All fields in table users
+	All pgm.Field = "users.*"
 	// ID field has db type "integer NOT NULL"
 	ID pgm.Field = "users.id"
 	// Name field has db type "character varying(255) NOT NULL"

playground/db/usersession/user_sessions.go

@@ -1,10 +1,12 @@
-// Code generated by db-gen. DO NOT EDIT.
+// Code generated by code.patial.tech/go/pgm/cmd DO NOT EDIT.
 
 package usersession
 
 import "code.patial.tech/go/pgm"
 
 const (
+	// All fields in table user_sessions
+	All pgm.Field = "user_sessions.*"
 	// ID field has db type "character varying NOT NULL"
 	ID pgm.Field = "user_sessions.id"
 	// CreatedAt field has db type "timestamp with time zone DEFAULT CURRENT_TIMESTAMP NOT NULL"

playground/qry_delete_test.go

@@ -8,9 +8,9 @@ import (
 )
 
 func TestDelete(t *testing.T) {
-	expected := "DELETE FROM users WHERE users.id = $1 AND users.status_id NOT IN($2)"
+	expected := "DELETE FROM users WHERE users.id = $1 AND users.status_id != ANY($2)"
 	got := db.User.Delete().
-		Where(user.ID.Eq(1), user.StatusID.NotIn(1, 2, 3)).
+		Where(user.ID.Eq(1), user.StatusID.NotAny(1, 2, 3)).
 		String()
 	if got != expected {
 		t.Errorf("got %q, want %q", got, expected)

playground/qry_insert_test.go

@@ -23,23 +23,6 @@ func TestInsertQuery(t *testing.T) {
 	}
 }
 
-func TestInsertSetMap(t *testing.T) {
-	got := db.User.Insert().
-		SetMap(map[pgm.Field]any{
-			user.Email:     "aa@aa.com",
-			user.Phone:     8889991234,
-			user.FirstName: "fname",
-			user.LastName:  "lname",
-		}).
-		Returning(user.ID).
-		String()
-
-	expected := "INSERT INTO users(email, phone, first_name, last_name) VALUES($1, $2, $3, $4) RETURNING id"
-	if got != expected {
-		t.Errorf("\nexpected: %q\ngot: %q", expected, got)
-	}
-}
-
 func TestInsertQuery2(t *testing.T) {
 	got := db.User.Insert().
 		Set(user.Email, "aa@aa.com").
@@ -53,7 +36,7 @@ func TestInsertQuery2(t *testing.T) {
 	}
 }
 
-// BenchmarkInsertQuery-12    	 1952412	       605.3 ns/op	    1144 B/op	      18 allocs/op
+// BenchmarkInsertQuery-12    	 2014519	       584.0 ns/op	    1144 B/op	      18 allocs/op
 func BenchmarkInsertQuery(b *testing.B) {
 	for b.Loop() {
 		_ = db.User.Insert().

playground/qry_select_test.go

@@ -28,7 +28,7 @@ func TestQryBuilder2(t *testing.T) {
 			),
 		).
 		Where(
-			user.LastName.NEq(7),
+			user.LastName.NotEq(7),
 			user.Phone.Like("%123%"),
 			user.UpdatedAt.IsNotNull(),
 			user.Email.NotInSubQuery(db.User.Select(user.ID).Where(user.ID.Eq(123))),
@@ -40,7 +40,7 @@ func TestQryBuilder2(t *testing.T) {
 	expected := "SELECT users.email, users.first_name FROM users JOIN user_sessions ON users.id = user_sessions.user_id" +
 		" JOIN branch_users ON users.id = branch_users.user_id WHERE users.id = $1 AND (users.status_id = $2 OR users.updated_at = $3)" +
 		" AND users.mfa_kind = $4 AND (users.first_name = $5 OR users.middle_name = $6) AND users.last_name != $7 AND users.phone" +
-		" LIKE $8 AND users.updated_at IS NOT NULL AND users.email NOT IN(SELECT users.id FROM users WHERE users.id = $9) LIMIT 10 OFFSET 100"
+		" LIKE $8 AND users.updated_at IS NOT NULL AND users.email != ANY(SELECT users.id FROM users WHERE users.id = $9) LIMIT 10 OFFSET 100"
 	if expected != got {
 		t.Errorf("\nexpected: %q\ngot: %q", expected, got)
 	}
@@ -60,7 +60,52 @@ func TestSelectWithHaving(t *testing.T) {
 	}
 }
 
-// BenchmarkSelect-12    	  668817	      1753 ns/op	    4442 B/op	      59 allocs/op
+func TestSelectDerived(t *testing.T) {
+	expected := "SELECT t.* FROM (SELECT users.*, ROW_NUMBER() OVER (PARTITION BY users.status_id ORDER BY users.created_at DESC) AS rn" +
+		" FROM users WHERE users.status_id = $1) AS t WHERE t.rn <= $2" +
+		" ORDER BY t.status_id, t.created_at DESC"
+
+	qry := db.User.
+		Select(user.All, user.CreatedAt.RowNumberDescPartionBy(user.StatusID, "rn")).
+		Where(user.StatusID.Eq(1))
+
+	tbl := db.DerivedTable("t", qry)
+	got := tbl.
+		Select(tbl.Field("*")).
+		Where(tbl.Field("rn").Lte(5)).
+		OrderBy(tbl.Field("status_id"), tbl.Field("created_at").Desc()).
+		String()
+
+	if expected != got {
+		t.Errorf("\nexpected: %q\n\ngot:      %q", expected, got)
+	}
+}
+
+func TestSelectWithJoin(t *testing.T) {
+	got := db.User.Select(user.Email, user.FirstName).
+		Join(db.UserSession, user.ID, usersession.UserID).
+		LeftJoin(db.BranchUser, user.ID, branchuser.UserID, pgm.Or(branchuser.RoleID.Eq("1"), branchuser.RoleID.Eq("2"))).
+		Where(
+			user.ID.Eq(3),
+			pgm.Or(
+				user.StatusID.Eq(4),
+				user.UpdatedAt.Eq(5),
+			),
+		).
+		Limit(10).
+		Offset(100).
+		String()
+
+	expected := "SELECT users.email, users.first_name " +
+		"FROM users JOIN user_sessions ON users.id = user_sessions.user_id " +
+		"LEFT JOIN branch_users ON users.id = branch_users.user_id AND (branch_users.role_id = $1 OR branch_users.role_id = $2) " +
+		"WHERE users.id = $3 AND (users.status_id = $4 OR users.updated_at = $5) " +
+		"LIMIT 10 OFFSET 100"
+	if expected != got {
+		t.Errorf("\nexpected: %q\ngot: %q", expected, got)
+	}
+}
+
 // BenchmarkSelect-12    	  638901	      1860 ns/op	    4266 B/op	      61 allocs/op
 func BenchmarkSelect(b *testing.B) {
 	for b.Loop() {
@@ -80,7 +125,7 @@ func BenchmarkSelect(b *testing.B) {
 				),
 			).
 			Where(
-				user.LastName.NEq(7),
+				user.LastName.NotEq(7),
 				user.Phone.Like("%123%"),
 				user.Email.NotInSubQuery(db.User.Select(user.ID).Where(user.ID.Eq(123))),
 			).

playground/qry_update_test.go

@@ -3,7 +3,6 @@ package playground
 import (
 	"testing"
 
-	"code.patial.tech/go/pgm"
 	"code.patial.tech/go/pgm/playground/db"
 	"code.patial.tech/go/pgm/playground/db/user"
 )
@@ -17,28 +16,7 @@ func TestUpdateQuery(t *testing.T) {
 			user.Email.Eq("aa@aa.com"),
 		).
 		Where(
-			user.StatusID.NEq(1),
-		).
-		String()
-
-	expected := "UPDATE users SET first_name=$1, middle_name=$2, last_name=$3 WHERE users.email = $4 AND users.status_id != $5"
-	if got != expected {
-		t.Errorf("\nexpected: %q\ngot: %q", expected, got)
-	}
-}
-
-func TestUpdateSetMap(t *testing.T) {
-	got := db.User.Update().
-		SetMap(map[pgm.Field]any{
-			user.FirstName:  "ankit",
-			user.MiddleName: "singh",
-			user.LastName:   "patial",
-		}).
-		Where(
-			user.Email.Eq("aa@aa.com"),
-		).
-		Where(
-			user.StatusID.NEq(1),
+			user.StatusID.NotEq(1),
 		).
 		String()
 
@@ -59,7 +37,7 @@ func BenchmarkUpdateQuery(b *testing.B) {
 				user.Email.Eq("aa@aa.com"),
 			).
 			Where(
-				user.StatusID.NEq(1),
+				user.StatusID.NotEq(1),
 			).
 			String()
 	}

pool.go

@@ -1,110 +0,0 @@
-// Patial Tech.
-// Author, Ankit Patial
-
-package pgm
-
-import (
-	"context"
-	"errors"
-	"log/slog"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"time"
-
-	"github.com/jackc/pgx/v5"
-	"github.com/jackc/pgx/v5/pgxpool"
-)
-
-var (
-	poolPGX           atomic.Pointer[pgxpool.Pool]
-	poolStringBuilder = sync.Pool{
-		New: func() any {
-			return new(strings.Builder)
-		},
-	}
-
-	ErrConnStringMissing = errors.New("connection string is empty")
-	ErrInitTX            = errors.New("failed to init db.tx")
-	ErrCommitTX          = errors.New("failed to commit db.tx")
-	ErrNoRows            = errors.New("no data found")
-)
-
-type Config struct {
-	ConnString      string
-	MaxConns        int32
-	MinConns        int32
-	MaxConnLifetime time.Duration
-	MaxConnIdleTime time.Duration
-}
-
-// InitPool will create new pgxpool.Pool and will keep it for its working
-func InitPool(conf Config) {
-	if conf.ConnString == "" {
-		panic(ErrConnStringMissing)
-	}
-
-	cfg, err := pgxpool.ParseConfig(conf.ConnString)
-	if err != nil {
-		panic(err)
-	}
-
-	if conf.MaxConns > 0 {
-		cfg.MaxConns = conf.MaxConns // 100
-	}
-
-	if conf.MinConns > 0 {
-		cfg.MinConns = conf.MaxConns // 5
-	}
-
-	if conf.MaxConnLifetime > 0 {
-		cfg.MaxConnLifetime = conf.MaxConnLifetime // time.Minute * 10
-	}
-
-	if conf.MaxConnIdleTime > 0 {
-		cfg.MaxConnIdleTime = conf.MaxConnIdleTime // time.Minute * 5
-	}
-
-	p, err := pgxpool.NewWithConfig(context.Background(), cfg)
-	if err != nil {
-		panic(err)
-	}
-
-	if err = p.Ping(context.Background()); err != nil {
-		panic(err)
-	}
-
-	poolPGX.Store(p)
-}
-
-// get string builder from pool
-func getSB() *strings.Builder {
-	return poolStringBuilder.Get().(*strings.Builder)
-}
-
-// put string builder back to pool
-func putSB(sb *strings.Builder) {
-	sb.Reset()
-	poolStringBuilder.Put(sb)
-}
-
-// GetPool instance
-func GetPool() *pgxpool.Pool {
-	return poolPGX.Load()
-}
-
-// BeginTx begins a pgx poll transaction
-func BeginTx(ctx context.Context) (pgx.Tx, error) {
-	tx, err := poolPGX.Load().Begin(ctx)
-	if err != nil {
-		slog.Error(err.Error())
-		return nil, errors.New("failed to open db tx")
-	}
-
-	return tx, err
-}
-
-// IsNotFound error check
-func IsNotFound(err error) bool {
-	return errors.Is(err, pgx.ErrNoRows)
-}

qry.go

@@ -7,156 +7,17 @@ import (
 	"context"
 	"strconv"
 	"strings"
+	"sync"
 
 	"github.com/jackc/pgx/v5"
 )
 
 type (
 	Clause interface {
+		Insert() InsertClause
 		Select(fields ...Field) SelectClause
-		// Insert() InsertSet
-		// Update() UpdateSet
-		// Delete() WhereOrExec
-	}
-
-	SelectClause interface {
-		// Join and Inner Join are same
-		Join(m Table, t1Field, t2Field Field) SelectClause
-		LeftJoin(m Table, t1Field, t2Field Field) SelectClause
-		RightJoin(m Table, t1Field, t2Field Field) SelectClause
-		FullJoin(m Table, t1Field, t2Field Field) SelectClause
-		CrossJoin(m Table) SelectClause
-		WhereClause
-		OrderByClause
-		GroupByClause
-		LimitClause
-		OffsetClause
-		Query
-		raw(prefixArgs []any) (string, []any)
-	}
-
-	WhereClause interface {
-		Where(cond ...Conditioner) AfterWhere
-	}
-
-	AfterWhere interface {
-		WhereClause
-		GroupByClause
-		OrderByClause
-		LimitClause
-		OffsetClause
-		Query
-	}
-
-	GroupByClause interface {
-		GroupBy(fields ...Field) AfterGroupBy
-	}
-
-	AfterGroupBy interface {
-		HavinClause
-		OrderByClause
-		LimitClause
-		OffsetClause
-		Query
-	}
-
-	HavinClause interface {
-		Having(cond ...Conditioner) AfterHaving
-	}
-
-	AfterHaving interface {
-		OrderByClause
-		LimitClause
-		OffsetClause
-		Query
-	}
-
-	OrderByClause interface {
-		OrderBy(fields ...Field) AfterOrderBy
-	}
-
-	AfterOrderBy interface {
-		LimitClause
-		OffsetClause
-		Query
-	}
-
-	LimitClause interface {
-		Limit(v int) AfterLimit
-	}
-
-	AfterLimit interface {
-		OffsetClause
-		Query
-	}
-
-	OffsetClause interface {
-		Offset(v int) AfterOffset
-	}
-
-	AfterOffset interface {
-		LimitClause
-		Query
-	}
-
-	Conditioner interface {
-		Condition(args *[]any, idx int) string
-	}
-
-	Insert interface {
-		Set(field Field, val any) InsertClause
-		SetMap(fields map[Field]any) InsertClause
-	}
-
-	InsertClause interface {
-		Insert
-		Returning(field Field) First
-		OnConflict(fields ...Field) Do
-		Execute
-		Stringer
-	}
-
-	Do interface {
-		DoNothing() Execute
-		DoUpdate(fields ...Field) Execute
-	}
-
-	Update interface {
-		Set(field Field, val any) UpdateClause
-		SetMap(fields map[Field]any) UpdateClause
-	}
-
-	UpdateClause interface {
-		Update
-		Where(cond ...Conditioner) WhereOrExec
-	}
-
-	WhereOrExec interface {
-		Where(cond ...Conditioner) WhereOrExec
-		Execute
-	}
-
-	Query interface {
-		First
-		All
-		Stringer
-	}
-
-	First interface {
-		First(ctx context.Context, dest ...any) error
-		FirstTx(ctx context.Context, tx pgx.Tx, dest ...any) error
-		Stringer
-	}
-
-	All interface {
-		// Query rows
-		//
-		// don't forget to close() rows
-		All(ctx context.Context, rows RowsCb) error
-		// Query rows
-		//
-		// don't forget to close() rows
-		AllTx(ctx context.Context, tx pgx.Tx, rows RowsCb) error
+		Update() UpdateClause
+		Delete() DeleteCluase
 	}
 
 	Execute interface {
@@ -169,26 +30,26 @@ type (
 		String() string
 	}
 
-	RowScanner interface {
-		Scan(dest ...any) error
+	Conditioner interface {
+		Condition(args *[]any, idx int) string
 	}
-
-	RowsCb func(row RowScanner) error
 )
 
-func joinFileds(fields []Field) string {
-	sb := getSB()
-	defer putSB(sb)
-	for i, f := range fields {
-		if i == 0 {
-			sb.WriteString(f.String())
-		} else {
-			sb.WriteString(", ")
-			sb.WriteString(f.String())
-		}
-	}
+var sbPool = sync.Pool{
+	New: func() any {
+		return new(strings.Builder)
+	},
+}
 
-	return sb.String()
+// get string builder from pool
+func getSB() *strings.Builder {
+	return sbPool.Get().(*strings.Builder)
+}
+
+// put string builder back to pool
+func putSB(sb *strings.Builder) {
+	sb.Reset()
+	sbPool.Put(sb)
 }
 
 func And(cond ...Conditioner) Conditioner {

qry_delete.go

@@ -7,6 +7,10 @@ import (
 )
 
 type (
+	DeleteCluase interface {
+		WhereOrExec
+	}
+
 	deleteQry struct {
 		table     string
 		condition []Conditioner
@@ -15,15 +19,6 @@ type (
 	}
 )
 
-func (t *Table) Delete() WhereOrExec {
-	qb := &deleteQry{
-		table: t.Name,
-		debug: t.debug,
-	}
-
-	return qb
-}
-
 func (q *deleteQry) Where(cond ...Conditioner) WhereOrExec {
 	q.condition = append(q.condition, cond...)
 	return q

qry_insert.go

@@ -12,7 +12,21 @@ import (
 	"github.com/jackc/pgx/v5"
 )
 
-type insertQry struct {
+type (
+	InsertClause interface {
+		Insert
+		Returning(field Field) First
+		OnConflict(fields ...Field) Do
+		Execute
+		Stringer
+	}
+
+	Insert interface {
+		Set(field Field, val any) InsertClause
+		SetMap(fields map[Field]any) InsertClause
+	}
+
+	insertQry struct {
 		returing   *string
 		onConflict *string
 
@@ -23,18 +37,8 @@ type insertQry struct {
 		vals   []string
 		args   []any
 		debug  bool
-}
-
-func (t *Table) Insert() Insert {
-	qb := &insertQry{
-		table:  t.Name,
-		fields: make([]string, 0, t.FieldCount),
-		vals:   make([]string, 0, t.FieldCount),
-		args:   make([]any, 0, t.FieldCount),
-		debug:  t.debug,
 	}
-	return qb
-}
+)
 
 func (q *insertQry) Set(field Field, val any) InsertClause {
 	q.fields = append(q.fields, field.Name())

qry_select.go

@@ -7,6 +7,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"slices"
 	"strconv"
 	"strings"
 
@@ -14,6 +15,125 @@ import (
 )
 
 type (
+	SelectClause interface {
+		// Join and Inner Join are same
+		Join(m Table, t1Field, t2Field Field, cond ...Conditioner) SelectClause
+		LeftJoin(m Table, t1Field, t2Field Field, cond ...Conditioner) SelectClause
+		RightJoin(m Table, t1Field, t2Field Field, cond ...Conditioner) SelectClause
+		FullJoin(m Table, t1Field, t2Field Field, cond ...Conditioner) SelectClause
+		CrossJoin(m Table) SelectClause
+		WhereClause
+		OrderByClause
+		GroupByClause
+		LimitClause
+		OffsetClause
+		Query
+		raw(prefixArgs []any) (string, []any)
+	}
+
+	WhereClause interface {
+		Where(cond ...Conditioner) AfterWhere
+	}
+
+	AfterWhere interface {
+		WhereClause
+		GroupByClause
+		OrderByClause
+		LimitClause
+		OffsetClause
+		Query
+	}
+
+	GroupByClause interface {
+		GroupBy(fields ...Field) AfterGroupBy
+	}
+
+	AfterGroupBy interface {
+		HavinClause
+		OrderByClause
+		LimitClause
+		OffsetClause
+		Query
+	}
+
+	HavinClause interface {
+		Having(cond ...Conditioner) AfterHaving
+	}
+
+	AfterHaving interface {
+		OrderByClause
+		LimitClause
+		OffsetClause
+		Query
+	}
+
+	OrderByClause interface {
+		OrderBy(fields ...Field) AfterOrderBy
+	}
+
+	AfterOrderBy interface {
+		LimitClause
+		OffsetClause
+		Query
+	}
+
+	LimitClause interface {
+		Limit(v int) AfterLimit
+	}
+
+	AfterLimit interface {
+		OffsetClause
+		Query
+	}
+
+	OffsetClause interface {
+		Offset(v int) AfterOffset
+	}
+
+	AfterOffset interface {
+		LimitClause
+		Query
+	}
+
+	Do interface {
+		DoNothing() Execute
+		DoUpdate(fields ...Field) Execute
+	}
+
+	Query interface {
+		First
+		All
+		Stringer
+		Bulder
+	}
+
+	RowScanner interface {
+		Scan(dest ...any) error
+	}
+
+	RowsCb func(row RowScanner) error
+
+	First interface {
+		First(ctx context.Context, dest ...any) error
+		FirstTx(ctx context.Context, tx pgx.Tx, dest ...any) error
+		Stringer
+	}
+
+	All interface {
+		// Query rows
+		//
+		// don't forget to close() rows
+		All(ctx context.Context, rows RowsCb) error
+		// Query rows
+		//
+		// don't forget to close() rows
+		AllTx(ctx context.Context, tx pgx.Tx, rows RowsCb) error
+	}
+
+	Bulder interface {
+		Build(needArgs bool) (qry string, args []any)
+	}
+
 	selectQry struct {
 		table   string
 		fields  []Field
@@ -23,8 +143,10 @@ type (
 		groupBy []Field
 		having  []Conditioner
 		orderBy []Field
+
 		limit  int
 		offset int
+
 		debug bool
 	}
 
@@ -51,34 +173,46 @@ const (
 	CondActionSubQuery
 )
 
-// Select clause
-func (t Table) Select(field ...Field) SelectClause {
-	qb := &selectQry{
-		table:  t.Name,
-		debug:  t.debug,
-		fields: field,
+func (q *selectQry) Join(t Table, t1Field, t2Field Field, cond ...Conditioner) SelectClause {
+	return q.buildJoin(t, "JOIN", t1Field, t2Field, cond...)
+}
+
+func (q *selectQry) LeftJoin(t Table, t1Field, t2Field Field, cond ...Conditioner) SelectClause {
+	return q.buildJoin(t, "LEFT JOIN", t1Field, t2Field, cond...)
+}
+
+func (q *selectQry) RightJoin(t Table, t1Field, t2Field Field, cond ...Conditioner) SelectClause {
+	return q.buildJoin(t, "RIGHT JOIN", t1Field, t2Field, cond...)
+}
+
+func (q *selectQry) FullJoin(t Table, t1Field, t2Field Field, cond ...Conditioner) SelectClause {
+	return q.buildJoin(t, "FULL JOIN", t1Field, t2Field, cond...)
+}
+
+func (q *selectQry) buildJoin(t Table, joinKW string, t1Field, t2Field Field, cond ...Conditioner) SelectClause {
+	str := joinKW + " " + t.Name + " ON " + t1Field.String() + " = " + t2Field.String()
+	if len(cond) == 0 { // Join with no condition
+		q.join = append(q.join, str)
+		return q
 	}
 
-	return qb
-}
+	// Join has condition(s)
+	sb := getSB()
+	defer putSB(sb)
+	sb.Grow(len(str) * 2)
 
-func (q *selectQry) Join(t Table, t1Field, t2Field Field) SelectClause {
-	q.join = append(q.join, "JOIN "+t.Name+" ON "+t1Field.String()+" = "+t2Field.String())
-	return q
-}
+	sb.WriteString(str + " AND ")
 
-func (q *selectQry) LeftJoin(t Table, t1Field, t2Field Field) SelectClause {
-	q.join = append(q.join, "LEFT JOIN "+t.Name+" ON "+t1Field.String()+" = "+t2Field.String())
-	return q
-}
+	var argIdx int
+	for i, c := range cond {
+		argIdx = len(q.args)
+		if i > 0 {
+			sb.WriteString(" AND ")
+		}
+		sb.WriteString(c.Condition(&q.args, argIdx))
+	}
 
-func (q *selectQry) RightJoin(t Table, t1Field, t2Field Field) SelectClause {
-	q.join = append(q.join, "RIGHT JOIN "+t.Name+" ON "+t1Field.String()+" = "+t2Field.String())
-	return q
-}
-
-func (q *selectQry) FullJoin(t Table, t1Field, t2Field Field) SelectClause {
-	q.join = append(q.join, "FULL JOIN "+t.Name+" ON "+t1Field.String()+" = "+t2Field.String())
+	q.join = append(q.join, sb.String())
 	return q
 }
 
@@ -163,6 +297,17 @@ func (q *selectQry) raw(prefixArgs []any) (string, []any) {
 }
 
 func (q *selectQry) String() string {
+	qry, _ := q.Build(false)
+	if q.debug {
+		fmt.Println("***")
+		fmt.Println(qry)
+		fmt.Printf("%+v\n", q.args)
+		fmt.Println("***")
+	}
+	return qry
+}
+
+func (q *selectQry) Build(needArgs bool) (qry string, args []any) {
 	sb := getSB()
 	defer putSB(sb)
 
@@ -228,14 +373,19 @@ func (q *selectQry) String() string {
 		sb.WriteString(strconv.Itoa(q.offset))
 	}
 
-	qry := sb.String()
+	qry = sb.String()
 	if q.debug {
 		fmt.Println("***")
 		fmt.Println(qry)
 		fmt.Printf("%+v\n", q.args)
 		fmt.Println("***")
 	}
-	return qry
+
+	if needArgs {
+		args = slices.Clone(q.args)
+	}
+
+	return
 }
 
 func (q *selectQry) averageLen() int {

qry_update.go

@@ -11,23 +11,30 @@ import (
 	"github.com/jackc/pgx/v5"
 )
 
-type updateQry struct {
+type (
+	Update interface {
+		Set(field Field, val any) UpdateClause
+		SetMap(fields map[Field]any) UpdateClause
+	}
+
+	UpdateClause interface {
+		Update
+		Where(cond ...Conditioner) WhereOrExec
+	}
+
+	WhereOrExec interface {
+		Where(cond ...Conditioner) WhereOrExec
+		Execute
+	}
+
+	updateQry struct {
 		table     string
 		cols      []string
 		condition []Conditioner
 		args      []any
 		debug     bool
-}
-
-func (t *Table) Update() Update {
-	qb := &updateQry{
-		table: t.Name,
-		debug: t.debug,
-		cols:  make([]string, 0, t.FieldCount),
-		args:  make([]any, 0, t.FieldCount),
 	}
-	return qb
-}
+)
 
 func (q *updateQry) Set(field Field, val any) UpdateClause {
 	col := field.Name()