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oracle 11g

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This commit is contained in:
Charlie
2024-05-10 11:28:44 +08:00
parent 184a8722d8
commit 2d3723822b
5 changed files with 141 additions and 93 deletions
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148
oracle.go
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@ -4,7 +4,6 @@ import (
"context"
"database/sql"
"fmt"
"log"
"regexp"
"strconv"
"strings"
@ -21,6 +20,8 @@ import (
"gorm.io/gorm/schema"
)
const RowNumberAliasForOracle11 = "ROW_NUM"
type Config struct {
DriverName string
DSN string
@ -51,7 +52,11 @@ func (d Dialector) Name() string {
}
func (d Dialector) Initialize(db *gorm.DB) (err error) {
db.NamingStrategy = Namer{db.NamingStrategy.(schema.NamingStrategy)}
db.NamingStrategy = Namer{
NamingStrategy: db.NamingStrategy,
DBName: d.DBName,
}
d.DefaultStringSize = 1024
// register callbacks
@ -64,10 +69,15 @@ func (d Dialector) Initialize(db *gorm.DB) (err error) {
d.DriverName = "godror"
// godror.Batch
if d.Conn != nil {
db.ConnPool = d.Conn
} else {
db.ConnPool, err = sql.Open(d.DriverName, d.DSN)
if err != nil {
return
}
}
err = db.ConnPool.QueryRowContext(context.Background(), "select version from product_component_version where rownum = 1").Scan(&d.DBVer)
if err != nil {
@ -96,7 +106,6 @@ func (d Dialector) ClauseBuilders() map[string]clause.ClauseBuilder {
"LIMIT": d.RewriteLimit,
}
}
}
func (d Dialector) RewriteLimit(c clause.Clause, builder clause.Builder) {
@ -121,9 +130,14 @@ func (d Dialector) RewriteLimit(c clause.Clause, builder clause.Builder) {
builder.WriteString(strconv.Itoa(offset))
builder.WriteString(" ROWS")
}
if limit := limit.Limit; *limit > 0 {
v := 0
if limit.Limit != nil {
v = *limit.Limit
}
if v > 0 {
builder.WriteString(" FETCH NEXT ")
builder.WriteString(strconv.Itoa(*limit))
builder.WriteString(strconv.Itoa(v))
builder.WriteString(" ROWS ONLY")
}
}
@ -131,34 +145,93 @@ func (d Dialector) RewriteLimit(c clause.Clause, builder clause.Builder) {
// Oracle11 Limit
func (d Dialector) RewriteLimit11(c clause.Clause, builder clause.Builder) {
if limit, ok := c.Expression.(clause.Limit); ok {
if stmt, ok := builder.(*gorm.Statement); ok {
limitsql := strings.Builder{}
if limit := limit.Limit; *limit > 0 {
if _, ok := stmt.Clauses["WHERE"]; !ok {
limitsql.WriteString(" WHERE ")
} else {
limitsql.WriteString(" AND ")
}
limitsql.WriteString("ROWNUM <= ")
limitsql.WriteString(strconv.Itoa(*limit))
}
if _, ok := stmt.Clauses["ORDER BY"]; !ok {
builder.WriteString(limitsql.String())
} else {
// "ORDER BY" before insert
sqltmp := strings.Builder{}
sqlold := stmt.SQL.String()
orderindx := strings.Index(sqlold, "ORDER BY") - 1
sqltmp.WriteString(sqlold[:orderindx])
sqltmp.WriteString(limitsql.String())
sqltmp.WriteString(sqlold[orderindx:])
log.Println(sqltmp.String())
stmt.SQL = sqltmp
}
}
limit, ok := c.Expression.(clause.Limit)
if !ok {
return
}
offsetRows := limit.Offset
hasOffset := offsetRows > 0
limitRows, hasLimit := d.getLimitRows(limit)
if !hasOffset && !hasLimit {
return
}
var stmt *gorm.Statement
if stmt, ok = builder.(*gorm.Statement); !ok {
return
}
if hasLimit && hasOffset {
subQuerySQL := fmt.Sprintf(
"SELECT * FROM (SELECT T.*, ROW_NUMBER() OVER (ORDER BY %s) AS %s FROM (%s) T) WHERE %s BETWEEN %d AND %d",
d.getOrderByColumns(stmt),
RowNumberAliasForOracle11,
strings.TrimSpace(stmt.SQL.String()),
RowNumberAliasForOracle11,
offsetRows+1,
offsetRows+limitRows,
)
stmt.SQL.Reset()
stmt.SQL.WriteString(subQuerySQL)
} else if hasLimit {
// 只有 Limit 的情况
subQuerySQL := fmt.Sprintf(
"SELECT * FROM (%s) WHERE ROWNUM <= %d",
strings.TrimSpace(stmt.SQL.String()),
limitRows,
)
// d.rewriteRownumStmt(stmt, builder, " <= ", limitRows)
stmt.SQL.Reset()
stmt.SQL.WriteString(subQuerySQL)
} else {
// 只有 Offset 的情况
// 偏移后取剩余所有记录
subQuerySQL := fmt.Sprintf(
"SELECT * FROM (SELECT T.*, ROW_NUMBER() OVER (ORDER BY %s) AS %s FROM (%s) T) WHERE %s > %d",
d.getOrderByColumns(stmt),
RowNumberAliasForOracle11,
strings.TrimSpace(stmt.SQL.String()),
RowNumberAliasForOracle11,
offsetRows+1,
)
stmt.SQL.Reset()
stmt.SQL.WriteString(subQuerySQL)
// d.rewriteRownumStmt(stmt, builder, " > ", offsetRows)
}
}
func (d Dialector) getOrderByColumns(stmt *gorm.Statement) string {
if orderByClause, ok := stmt.Clauses["ORDER BY"]; ok {
var orderBy clause.OrderBy
if orderBy, ok = orderByClause.Expression.(clause.OrderBy); ok && len(orderBy.Columns) > 0 {
orderByBuilder := strings.Builder{}
for i, column := range orderBy.Columns {
if i > 0 {
orderByBuilder.WriteString(", ")
}
orderByBuilder.WriteString(column.Column.Name)
if column.Desc {
orderByBuilder.WriteString(" DESC")
}
}
return orderByBuilder.String()
}
}
return "NULL"
}
func (d Dialector) getLimitRows(limit clause.Limit) (limitRows int, hasLimit bool) {
if l := limit.Limit; l != nil {
limitRows = *l
hasLimit = limitRows > 0
}
return
}
func (d Dialector) DefaultValueOf(*schema.Field) clause.Expression {
return clause.Expr{SQL: "VALUES (DEFAULT)"}
}
@ -181,7 +254,14 @@ func (d Dialector) BindVarTo(writer clause.Writer, stmt *gorm.Statement, v inter
}
func (d Dialector) QuoteTo(writer clause.Writer, str string) {
writer.WriteString(str)
if str != "" && IsReservedWord(str) {
writer.WriteByte('"')
writer.WriteString(str)
writer.WriteByte('"')
} else {
writer.WriteString(str)
}
}
var numericPlaceholder = regexp.MustCompile(`:(\d+)`)
@ -201,9 +281,7 @@ func (d Dialector) Explain(sql string, vars ...interface{}) string {
}
func (d Dialector) DataTypeOf(field *schema.Field) string {
if _, found := field.TagSettings["RESTRICT"]; found {
delete(field.TagSettings, "RESTRICT")
}
delete(field.TagSettings, "RESTRICT")
var sqlType string