B
    `:                 @   s   d dl Z d dlZd dlZd dlmZ d dlmZ d dlmZ d dl	m
Z
 d dlmZmZmZ d dlmZ d dlmZ d d	lmZ d d
lmZmZmZ d dlmZ d dlmZ G dd deZdS )    N)	lru_cache)chain)settings)
FieldError)DatabaseErrorNotSupportedErrormodels)BaseDatabaseOperations)Col)timezone)
parse_dateparse_datetime
parse_time)duration_microseconds)cached_propertyc                   sd  e Zd ZdZdddZdZdd Zdd Zd	d
 Zdd Z	dd Z
dd Zdd Zdd Zdd Zdd Zdd Zdd Zdd Zdd  Zd!d" Zd#d$ Zd%d& Zd'd( Zd)d* Zed+d, Zd-d-d.d/d0Zd1d2 Zd3d4 Zd5d6 Z fd7d8Zd9d: Z d;d< Z!d=d> Z"d?d@ Z#dAdB Z$dCdD Z%dEdF Z& fdGdHZ'dIdJ Z(dKdL Z)dMdN Z*dQ fdOdP	Z+  Z,S )RDatabaseOperationstextZTEXT)	DateFieldDateTimeFieldzEXPLAIN QUERY PLANc             C   s:   t |dkrdS t |dkr.| jjjt | S t |S dS )z
        SQLite has a compile-time default (SQLITE_LIMIT_VARIABLE_NUMBER) of
        999 variables per query.

        If there's only a single field to insert, the limit is 500
        (SQLITE_MAX_COMPOUND_SELECT).
           i  N)len
connectionfeaturesZmax_query_params)selffieldsobjs r   T/home/dcms/DCMS/lib/python3.7/site-packages/django/db/backends/sqlite3/operations.pybulk_batch_size   s
    z"DatabaseOperations.bulk_batch_sizec          
   C   s   t jt jt jf}t jt jt jt jf}t||rvxF|	 D ]:}y
|j
}W n ttfk
r^   Y q8X t||r8tdq8W t|t jr|jrt|jdkrtdd S )Nz{You cannot use Sum, Avg, StdDev, and Variance aggregations on date/time fields in sqlite3 since date/time is saved as text.r   zTSQLite doesn't support DISTINCT on aggregate functions accepting multiple arguments.)r   r   r   	TimeFieldZSumZAvgZVarianceZStdDev
isinstanceZget_source_expressionsoutput_fieldAttributeErrorr   r   Z	AggregateZdistinctr   Zsource_expressions)r   
expressionZ
bad_fieldsZbad_aggregatesexprr!   r   r   r   check_expression_support)   s     



z+DatabaseOperations.check_expression_supportc             C   s   d|  |f S )z
        Support EXTRACT with a user-defined function django_date_extract()
        that's registered in connect(). Use single quotes because this is a
        string and could otherwise cause a collision with a field name.
        zdjango_date_extract('%s', %s))lower)r   lookup_type
field_namer   r   r   date_extract_sqlE   s    z#DatabaseOperations.date_extract_sqlc             C   s   t t|S )N)strr   )r   	timedeltar   r   r   date_interval_sqlM   s    z$DatabaseOperations.date_interval_sqlc             C   s   |S )z>Do nothing since formatting is handled in the custom function.r   )r   sqlr   r   r   format_for_duration_arithmeticP   s    z1DatabaseOperations.format_for_duration_arithmeticc             C   s   d|  |f S )Nzdjango_date_trunc('%s', %s))r&   )r   r'   r(   r   r   r   date_trunc_sqlT   s    z!DatabaseOperations.date_trunc_sqlc             C   s   d|  |f S )Nzdjango_time_trunc('%s', %s))r&   )r   r'   r(   r   r   r   time_trunc_sqlW   s    z!DatabaseOperations.time_trunc_sqlc             C   s   t jrd| d| jj fS dS )Nz'%s')NULLr1   )r   USE_TZr   Ztimezone_name)r   tznamer   r   r   _convert_tznames_to_sqlZ   s    z*DatabaseOperations._convert_tznames_to_sqlc             C   s   d|f|  | S )Nz%django_datetime_cast_date(%s, %s, %s))r4   )r   r(   r3   r   r   r   datetime_cast_date_sql_   s    z)DatabaseOperations.datetime_cast_date_sqlc             C   s   d|f|  | S )Nz%django_datetime_cast_time(%s, %s, %s))r4   )r   r(   r3   r   r   r   datetime_cast_time_sqld   s    z)DatabaseOperations.datetime_cast_time_sqlc             C   s   d|  |f| | S )Nz)django_datetime_extract('%s', %s, %s, %s))r&   r4   )r   r'   r(   r3   r   r   r   datetime_extract_sqli   s    z'DatabaseOperations.datetime_extract_sqlc             C   s   d|  |f| | S )Nz'django_datetime_trunc('%s', %s, %s, %s))r&   r4   )r   r'   r(   r3   r   r   r   datetime_trunc_sqln   s    z%DatabaseOperations.datetime_trunc_sqlc             C   s   d|  |f S )Nzdjango_time_extract('%s', %s))r&   )r   r'   r(   r   r   r   time_extract_sqls   s    z#DatabaseOperations.time_extract_sqlc             C   s   dS )Nr1   r   )r   r   r   r   pk_default_valuev   s    z#DatabaseOperations.pk_default_valuec             C   s   d}t ||krPd}x6tdt ||D ]"}||||  }|| |7 }q&W |S dddgt |  }| jj }z||| S |  X dS )zV
        Only for last_executed_query! Don't use this to execute SQL queries!
        i  r   r   zSELECT z, zQUOTE(?)N)	r   range%_quote_params_for_last_executed_queryjoinr   cursorexecuteZfetchoneclose)r   paramsZ
BATCH_SIZEresultsindexchunkr-   r>   r   r   r   r<   y   s    	z8DatabaseOperations._quote_params_for_last_executed_queryc             C   sR   |rJt |ttfr| |}n$t| }| |}tt||}|| S |S d S )N)r    listtupler<   valuesdictzip)r   r>   r-   rA   rG   r   r   r   last_executed_query   s    
z&DatabaseOperations.last_executed_queryc             C   s    | dr|dr|S d| S )N"z"%s")
startswithendswith)r   namer   r   r   
quote_name   s    zDatabaseOperations.quote_namec             C   s   dS )Nr   )r   r   r   r   no_limit_value   s    z!DatabaseOperations.no_limit_valuec          	   C   sB   d}|ddf}| j   }|||}dd | D S Q R X d S )Nz
        WITH tables AS (
            SELECT %s name
            UNION
            SELECT sqlite_master.name
            FROM sqlite_master
            JOIN tables ON (sql REGEXP %s || tables.name || %s)
        ) SELECT name FROM tables;
        z(?i)\s+references\s+("|\')?z("|\')?\s*\(c             S   s   g | ]}|d  qS )r   r   ).0rowr   r   r   
<listcomp>   s    z9DatabaseOperations.__references_graph.<locals>.<listcomp>)r   r>   r?   Zfetchall)r   Z
table_namequeryrA   r>   rB   r   r   r   Z__references_graph   s    	z%DatabaseOperations.__references_graphc             C   s   t dd| jS )Ni   )maxsize)r   %_DatabaseOperations__references_graph)r   r   r   r   _references_graph   s    z$DatabaseOperations._references_graphF)reset_sequencesallow_cascadec               s`   |r$|r$t t fdd|D } fdd|D }|r\dd |D }| | |S )Nc             3   s   | ]}  |V  qd S )N)rX   )rR   table)r   r   r   	<genexpr>   s    z/DatabaseOperations.sql_flush.<locals>.<genexpr>c          
      s2   g | ]*}d  d d |f qS )z	%s %s %s;DELETEZFROM)SQL_KEYWORD	SQL_FIELDrO   )rR   r[   )r   styler   r   rT      s   z0DatabaseOperations.sql_flush.<locals>.<listcomp>c             S   s   g | ]}d |iqS )r[   r   )rR   r[   r   r   r   rT      s    )setr   from_iterableextendsequence_reset_by_name_sql)r   r`   ZtablesrY   rZ   r-   	sequencesr   )r   r`   r   	sql_flush   s    zDatabaseOperations.sql_flushc             C   sn   |sg S d| d|| d| d|| d| d|| d| dd	d
d |D f gS )Nz%s %s %s %s = 0 %s %s %s (%s);ZUPDATEZsqlite_sequenceZSETseqZWHERErN   INz, c             S   s   g | ]}d |d  qS )z'%s'r[   r   )rR   Zsequence_infor   r   r   rT      s    zADatabaseOperations.sequence_reset_by_name_sql.<locals>.<listcomp>)r^   Z	SQL_TABLErO   r_   r=   )r   r`   re   r   r   r   rd      s    z-DatabaseOperations.sequence_reset_by_name_sqlc             C   sL   |d krd S t |dr|S t|rDtjr<t|| jj}ntdt|S )Nresolve_expressionzNSQLite backend does not support timezone-aware datetimes when USE_TZ is False.)	hasattrr   is_awarer   r2   Z
make_naiver   
ValueErrorr*   )r   valuer   r   r   adapt_datetimefield_value   s    

z,DatabaseOperations.adapt_datetimefield_valuec             C   s4   |d krd S t |dr|S t|r,tdt|S )Nri   z5SQLite backend does not support timezone-aware times.)rj   r   rk   rl   r*   )r   rm   r   r   r   adapt_timefield_value   s    

z(DatabaseOperations.adapt_timefield_valuec                s   t  |}|j }|dkr,|| j np|dkrB|| j nZ|dkrX|| j nD|dkrr|| | n*|dkr|| j	 n|dkr|| j
 |S )Nr   r   r   ZDecimalFieldZ	UUIDField)ZNullBooleanFieldZBooleanField)superget_db_convertersr!   Zget_internal_typeappendconvert_datetimefield_valueconvert_datefield_valueconvert_timefield_valueget_decimalfield_converterconvert_uuidfield_valueconvert_booleanfield_value)r   r#   
convertersinternal_type)	__class__r   r   rq     s    
z$DatabaseOperations.get_db_convertersc             C   s@   |d k	r<t |tjst|}tjr<t|s<t|| jj}|S )N)	r    datetimer   r   r2   r   rk   Z
make_awarer   )r   rm   r#   r   r   r   r   rs     s    z.DatabaseOperations.convert_datetimefield_valuec             C   s    |d k	rt |tjst|}|S )N)r    r|   dater   )r   rm   r#   r   r   r   r   rt      s    z*DatabaseOperations.convert_datefield_valuec             C   s    |d k	rt |tjst|}|S )N)r    r|   timer   )r   rm   r#   r   r   r   r   ru   &  s    z*DatabaseOperations.convert_timefield_valuec                sN   t jddj t|tr>t d|jj  fdd}n fdd}|S )N   )precr   c                s"   | d k	r | j |jjdS d S )N)context)quantizer!   r   )rm   r#   r   )create_decimalquantize_valuer   r   	converter3  s    z@DatabaseOperations.get_decimalfield_converter.<locals>.converterc                s   | d k	r | S d S )Nr   )rm   r#   r   )r   r   r   r   7  s    )	decimalContextcreate_decimal_from_floatr    r
   Decimalscalebr!   Zdecimal_places)r   r#   r   r   )r   r   r   rv   ,  s    
z-DatabaseOperations.get_decimalfield_converterc             C   s   |d k	rt |}|S )N)uuidUUID)r   rm   r#   r   r   r   r   rw   <  s    
z*DatabaseOperations.convert_uuidfield_valuec             C   s   |dkrt |S |S )N)r   r   )bool)r   rm   r#   r   r   r   r   rx   A  s    z-DatabaseOperations.convert_booleanfield_valuec             C   s   d dd |D S )Nz UNION ALL c             s   s   | ]}d d | V  qdS )z	SELECT %sz, N)r=   )rR   rS   r   r   r   r\   F  s   z5DatabaseOperations.bulk_insert_sql.<locals>.<genexpr>)r=   )r   r   Zplaceholder_rowsr   r   r   bulk_insert_sqlD  s    z"DatabaseOperations.bulk_insert_sqlc                s:   |dkrdd | S |dkr,dd | S t ||S )N^z	POWER(%s),#z
BITXOR(%s))r=   rp   combine_expression)r   	connectorsub_expressions)r{   r   r   r   J  s
    z%DatabaseOperations.combine_expressionc             C   sD   |dkrt d| d| g| }t|dkr6tddd| S )N)+-z$Invalid connector for timedelta: %s.z'%s'   z)Too many params for timedelta operations.zdjango_format_dtdelta(%s)z, )r   r   rl   r=   )r   r   r   Z	fn_paramsr   r   r   combine_duration_expressionS  s    z.DatabaseOperations.combine_duration_expressionc             C   s   dS )N)NNr   )r   rz   r   r   r   integer_field_range[  s    z&DatabaseOperations.integer_field_rangec       	      C   s@   |\}}|\}}||}|dkr0d||f |fS d||f |fS )Nr   zdjango_time_diff(%s, %s)zdjango_timestamp_diff(%s, %s)r   )	r   rz   lhsrhsZlhs_sqlZ
lhs_paramsZrhs_sqlZ
rhs_paramsrA   r   r   r   subtract_temporals_  s    z%DatabaseOperations.subtract_temporalsc                s   |rdS t  |S )NzINSERT OR IGNORE INTO)rp   insert_statement)r   Zignore_conflicts)r{   r   r   r   g  s    z#DatabaseOperations.insert_statement)F)-__name__
__module____qualname__Z"cast_char_field_without_max_lengthZcast_data_typesZexplain_prefixr   r%   r)   r,   r.   r/   r0   r4   r5   r6   r7   r8   r9   r:   r<   rJ   rO   rQ   rW   r   rX   rf   rd   rn   ro   rq   rs   rt   ru   rv   rw   rx   r   r   r   r   r   r   __classcell__r   r   )r{   r   r      sR   	r   )r|   r   r   	functoolsr   	itertoolsr   Zdjango.confr   Zdjango.core.exceptionsr   Z	django.dbr   r   r   Z"django.db.backends.base.operationsr	   Zdjango.db.models.expressionsr
   Zdjango.utilsr   Zdjango.utils.dateparser   r   r   Zdjango.utils.durationr   Zdjango.utils.functionalr   r   r   r   r   r   <module>   s   