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  • Mysql 常用函数集

    1.分类导航

    一共分为5类函数 
    1. 字符型函数
    2. 数值型函数
    3. 日期型函数
    4. 统计型函数
    5. 其它型函数

    2.字符型函数[约48个]

    ascii(str)
    
    bin(n)
    
    bit_length(str)
    
    char(n,... [using charset])
    
    character_length(str)
    
    char_length(str)
    
    compress(string_to_compress)
    
    concat_ws(separator,str1,str2,...)
    
    conv(n,from_base,to_base)
    
    elt(n,str1,str2,str3,...)
    
    export_set(bits,on,off[,separator[,number_of_bits]])
    
    field(str,str1,str2,str3,...)
    
    find_in_set(str,strlist)
    
    hex(n_or_s)
    
    insert(str,pos,len,newstr)
    
    instr(str,substr)
    
    lcase(str)
    
    left(str,len)
    
    length(str)
    
    load_file(file_name)
    
    locate(substr,str) , locate(substr,str,pos)
    
    lower(str)
    
    lpad(str,len,padstr)
    
    ltrim(str)
    
    make_set(bits,str1,str2,...)
    
    mid(str,pos,len)
    
    oct(n)
    
    octet_length(str)
    
    ord(str)
    
    position(substr in str)
    
    quote(str)
    
    repeat(str,count)
    
    replace(str,from_str,to_str)
    
    reverse(str)
    
    right(str,len)
    
    rpad(str,len,padstr)
    
    rtrim(str)
    
    soundex(str)
    
    space(n)
    
    strcmp(expr1,expr2)
    
    substring(str,pos) , substring(str from pos) substring(str,pos,len) , substring(str from pos for len)
    
    substring_index(str,delim,count)
    
    trim([{both | leading | trailing} [remstr] from] str) trim(remstr from] str)
    
    ucase(str)
    
    uncompress(string_to_uncompress)
    
    uncompressed_length(compressed_string)
    
    unhex(str)
    
    upper(str)

    3.数值型函数[约25个]

    abs(x)
    
    acos(x)
    
    asin(x)
    
    atan(x)
    
    atan2(y,x)
    
    ceiling(x) ceil(x)
    
    cos(x)
    
    cot(x)
    
    crc32(expr)
    
    degrees(x)
    
    div
    
    exp(x)
    
    floor(x)
    
    log10(x)
    
    log2(x)
    
    mod(n,m) , n % m n mod m
    
    pi()
    
    pow(x,y) , power(x,y)
    
    radians(x)
    
    rand() rand(n)
    
    round(x) round(x,d)
    
    sign(x)
    
    sin(x)
    
    sqrt(x)
    
    tan(x)

    4.日期型函数[约65个]

    adddate(date,interval expr type)
    
    adddate(expr,days)
    
    addtime(expr,expr2)
    
    convert_tz(dt,from_tz,to_tz)
    
    curdate()
    
    current_date()
    
    current_time()
    
    current_timestamp()
    
    curtime()
    
    date(expr)
    
    datediff(expr,expr2)
    
    date_add(date,interval expr type) 
    
    date_format(date,format)
    
    date_add(date,interval expr type) 
    
    day(date)
    
    dayname(date)
    
    dayofweek(date)
    
    dayofyear(date)
    
    extract(type from date)
    
    dayofmonth(date)
    
    from_days(n)
    
    from_unixtime(unix_timestamp)
    
    from_unixtime(unix_timestamp,format)
    
    get_format(date|time|datetime, 'eur'|'usa'|'jis'|'iso'|'internal')
    
    hour(time)
    
    last_day(date)
    
    ln(x)
    
    localtime()
    
    localtimestamp()
    
    log(x) log(b,x)
    
    makedate(year,dayofyear)
    
    maketime(hour,minute,second)
    
    microsecond(expr)
    
    minute(time)
    
    month(date)
    
    monthname(date)
    
    now()
    
    period_add(p,n)
    
    period_diff(p1,p2)
    
    quarter(date)
    
    second(time)
    
    sec_to_time(seconds)
    
    str_to_date(str,format)
    
    subdate(date,interval expr type) subdate(expr,days)
    
    subtime(expr,expr2)
    
    sysdate()
    
    time(expr)
    
    timediff(expr,expr2)
    
    timestampadd(interval,int_expr,datetime_expr)
    
    timestampdiff(interval,datetime_expr1,datetime_expr2)
    
    time_format(time,format)
    
    time_to_sec(time)
    
    to_days(date)
    
    truncate(x,d)
    
    unix_timestamp()
    
    unix_timestamp(date)
    
    utc_date()
    
    utc_time()
    
    utc_timestamp()
    
    week(date[,mode])
    
    weekday(date)
    
    weekofyear(date)
    
    year(date)
    
    yearweek(date)
    
    yearweek(date,start)

    5.统计型函数[约14个]

    avg([distinct] expr)
    
    bit_and(expr)
    
    bit_or(expr)
    
    bit_xor(expr)
    
    count(distinct expr,[expr...])
    
    group_concat(expr)
    
    min([distinct] expr), max([distinct] expr)
    
    std(expr) stddev(expr)
    
    stddev_pop(expr)
    
    stddev_samp(expr)
    
    sum([distinct] expr)
    
    variance(expr)
    
    var_pop(expr)
    
    var_samp(expr)

    6.其它型函数[约44个]

    aes_encrypt(str,key_str) , aes_decrypt(crypt_str,key_str)
    
    benchmark(count,expr)
    
    binary
    
    bit_count(n)
    
    cast(expr as type), convert(expr,type) , convert(expr using transcoding_name)
    
    collation(str)
    
    connection_id()
    
    current_user()
    
    database()
    
    decode(crypt_str,pass_str)
    
    default(col_name)
    
    des_decrypt(crypt_str[,key_str])
    
    des_encrypt(str[,(key_num|key_str)])
    
    encode(str,pass_str)
    
    encrypt(str[,salt])
    
    format(x,d)
    
    found_rows()
    
    get_lock(str,timeout)
    
    if(expr1,expr2,expr3)
    
    ifnull(expr1,expr2)
    
    inet_aton(expr)
    
    inet_ntoa(expr)
    
    isnull(expr)
    
    is_free_lock(str)
    
    is_used_lock(str)
    
    master_pos_wait(log_name,log_pos[,timeout])
    
    md5(str)
    
    name_const(name,value)
    
    nullif(expr1,expr2)
    
    old_password(str)
    
    password(str)
    
    release_lock(str)
    
    row_count()
    
    schema()
    
    session_user()
    
    sha1(str) sha(str)
    
    sleep(duration)
    
    system_user()
    
    timestamp(expr) 
    
    timestamp(expr,expr2)
    
    user()
    
    uuid()
    
    values(col_name)
    
    version()

    转:https://blog.csdn.net/qq_15071263/article/details/79033856

    参考:https://blog.csdn.net/sinat_38899493/article/details/78710482

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  • 原文地址:https://www.cnblogs.com/fps2tao/p/9038601.html
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